Feedback: Units

[Simon_Jester]

A few thoughts on ranged combat.

I would suggest that if you are going to have units that just bombard such as the Battering Ram, then early units such as Catapults not be able to both bombard and do ranged attacks.

Agreed. Catapults really weren't that effective at reducing heavy fixed fortifications, not without ridiculously protracted sieges. Rams and other siege engines designed to deliver troops 'up close and personal' were vitally necessary to reduce a defender's tactical advantage and get the besieging army into position to attack the enemy on equal terms- which is the real point of "bombardment" anyway.

Also I suggest that if Skimishers have a chance to do collateral damage, Catapults and other early units should not be able to do collateral damage.

Fair. Collateral damage can be either widespread, indiscriminate bombardment or damage to the logistics of a defending force (when you think about it- this is how cavalry's flank attack damage works, sort of). Skirmishers would actually be about the only way to do this in ancient times; mechanical artillery of the pre-gunpowder era just isn't powerful enough to devastate armies indiscriminately the way even something as crude as Napoleonic grand batteries could.

While it is not a perfect fix, perhaps every time you fire or use a battering ram, catapult, etc., they take a fixed amount of damage (wear and tear that has to be repaired.) This would slow down their use somewhat.

I don't like it. For rams, if they're doing too much damage to fortifications, just reduce the amount of damage they can do to fortifications and don't fool around with damage mechanics (which can be viciously punitive in ancient times in enemy territory, since you have no medics).

For catapults and ranged attack units in general... I sort of see it, you can make a case for it. I don't know.

I thought it would be useful to republish these posts.

My original argument against Siege units, some two months ago:

I want to keep siege units- it's just a question of making them useful without making them overpowering. We might want to consider reducing the bombardment-resistance granted by City Walls and Castles, too; as it stands it can take forever to reduce city defenses of a large urban area, turn after turn after turn. This doesn't really serve a useful purpose in my opinion.

Limiting siege unit availability is tricky- the cap should probably increase over time just so that modern armies can have artillery commensurate with the scale of their infantry, armor, and other assets. Artillery-type units should be balanced well enough that you don't need a highly restrictive cap on it.

Also, artillery caps lend themselves to keeping obsolete artillery units around longer while building new replacements, although that's a pretty weird strategy for maxing out your reserve artillery arsenal. Can you stop someone from upgrading, say, Cannon -> Artillery if the civilization already has the maximum allowed number of Artillery units?

And the first detailed outline of possible Skirmisher units, by Simon Jester:

Between those posts and this thread, we've come up with some pretty good ideas.
We can't implement all of them; so I guess the next step is to put forward concrete proposals for revised Siege and Skirmisher units.
As I see it, we are limited chiefly by:

• the ability of the AI to understand and use new units and mechanics; and
• the limited availability of unit artwork for all civilizations.

• I know Xyth considers artwork to be very important, and I don't think there's anything fundamentally wrong with that. But we need to consider whether it's more important to get the mechanics working first and worry about the artwork second, or the other way around.
  
  Xyth doesn't agonize about finding authentically Japanese and British and German and Russian battleships to replace the generic Iowa-class battleship model used by the vanilla BtS game. It's not the end of the world if he uses a generic Sharpshooter unit.

 

[Xyth]

OK that is a good point: to offset this I suggest that in addition to the +1 , add also a -1 per citizen specialist.

I've not tested it or anything but I suspect that -1 food would deter the AI from ever settling their workers.

Also as an aside does anyone else think that we need ways like buildings for cities to boost their food output similar to the klin boosting ?

We've got to be careful with food bonuses, they can be quite unbalancing if distributed too liberally. It's important that growth doesn't ramp up too quickly too early. We'll also need to determine how all the health/unhealthiness changes are working first.

What if we limit the ranged attack max damage further, at least for most units capable of doing it?

This does seem like a reasonable option.

I would suggest that if you are going to have units that just bombard such as the Battering Ram, then early units such as Catapults not be able to both bombard and do ranged attacks.

Agreed. Catapults really weren't that effective at reducing heavy fixed fortifications, not without ridiculously protracted sieges. Rams and other siege engines designed to deliver troops 'up close and personal' were vitally necessary to reduce a defender's tactical advantage and get the besieging army into position to attack the enemy on equal terms- which is the real point of "bombardment" anyway.

This is pretty much what I originally envisioned. The rams and towers do one role, the catapults and trebuchets the other. Once you reach the gunpowder era you get units that can do both.

While it is not a perfect fix, perhaps every time you fire or use a battering ram, catapult, etc., they take a fixed amount of damage (wear and tear that has to be repaired.) This would slow down their use somewhat.

I wouldn't be able to make the AI understand this so we wouldn't be able to use it as a major limiting factor. In which case it's probably not worth the effort unfortunately.

Also I suggest that if Skimishers have a chance to do collateral damage, Catapults and other early units should not be able to do collateral damage.

Fair. Collateral damage can be either widespread, indiscriminate bombardment or damage to the logistics of a defending force (when you think about it- this is how cavalry's flank attack damage works, sort of). Skirmishers would actually be about the only way to do this in ancient times; mechanical artillery of the pre-gunpowder era just isn't powerful enough to devastate armies indiscriminately the way even something as crude as Napoleonic grand batteries could.

I'd like to see Archery units do collateral damage, they make the most sense to me for this role. I'm not sure on (early) Siege and Skirmisher though. I'm also not sure how this would translate to the gunpowder era.

Limiting siege unit availability is tricky- the cap should probably increase over time just so that modern armies can have artillery commensurate with the scale of their infantry, armor, and other assets. Artillery-type units should be balanced well enough that you don't need a highly restrictive cap on it.

Also, artillery caps lend themselves to keeping obsolete artillery units around longer while building new replacements, although that's a pretty weird strategy for maxing out your reserve artillery arsenal. Can you stop someone from upgrading, say, Cannon -> Artillery if the civilization already has the maximum allowed number of Artillery units?

I'd like to avoid using unit caps. For a start they don't scale with mapsize and then there are upgrade issues like you describe as well. A cap means that the unit in question is inherently imbalanced anyway.

I know Xyth considers artwork to be very important, and I don't think there's anything fundamentally wrong with that. But we need to consider whether it's more important to get the mechanics working first and worry about the artwork second, or the other way around.

I think we can and should get the mechanics working with the units we have already, and avoid the art issue altogether. At least for now.

Xyth doesn't agonize about finding authentically Japanese and British and German and Russian battleships to replace the generic Iowa-class battleship model used by the vanilla BtS game. It's not the end of the world if he uses a generic Sharpshooter unit.

I'd actually like to add some limited diversity to the modern vehicle units, it's just not a high priority (mainly because I lack the requisite knowledge). Having generic vehicles is quite different from generic human units though. To add a new human unit there needs to be an absolute minimum of 5 versions of it (European, African, Middle Eastern, East Asian, Native/Meso American), though it's not so bad in the Industrial and Modern era when uniforms become more 'uniform'.

 

[Howard Mahler]

Tamil ironclads are often showing up as huge in my current game, about 5 times the size they should be.

I do not know if this is Tamil only or if it affects other civs.

 

[KaneofEgypt]

Actually, the same thing with the ironclads is happening to me while playing as the Chinese, so this is definitely a widespread issue.

Also an issue is that if I set a unit to sentry or fortify, they change their appearance to whatever I believe was the base of their art work. A Chinese rifleman will change to an Oromo warrior moments after sleeping, or a Chinese horseman's horse will turn from black to white.

 

[Xyth]

Tamil ironclads are often showing up as huge in my current game, about 5 times the size they should be.

I do not know if this is Tamil only or if it affects other civs.

Actually, the same thing with the ironclads is happening to me while playing as the Chinese, so this is definitely a widespread issue.

Hmm mysterious, they're showing up at a sensible size for me. These giant ironclads, are they the old BTS model or the new one with masts and such?

Also an issue is that if I set a unit to sentry or fortify, they change their appearance to whatever I believe was the base of their art work. A Chinese rifleman will change to an Oromo warrior moments after sleeping, or a Chinese horseman's horse will turn from black to white.

You need to disable Frozen Animations. That setting is not compatible with any mod that uses cultural unit art.

 

[Azoth]

Here, as promised, are some proposals on Siege and Skirmisher units.

Option A
Summary
Ranged attacks are removed. Siege units are capable of low collateral damage and have reduced base Strength but increased withdrawal chance.
Walls are less resistant to bombardment. Skirmisher units target the weakest unit in a stack.

Details
Siege units can take City Raider, Drill, Barrage, and Accuracy promotions. They cannot take Combat, Medic, or March promotions. They are redesigned as follows:
Battering Ram, Strength 3, cannot attack, bombard 8% city defense/turn
Siege Tower, Strength 6, cannot attack, free Medic I, bombard 16% city defense/turn

Catapult, Strength 3, +50% city attack, max 20% collateral damage, 80% withdrawal chance
Trebuchet, Strength 4, +100% city attack, max 25% collateral damage, 75% withdrawal chance

Bombard, Strength 6, +50% city attack, max 20% collateral damage, 80% withdrawal chance, bombard 12% city defense/turn, ignores Walls and Castles
Cannon, Strength 8, +50% city attack, max 25% collateral damage, 75% withdrawal chance, bombard 12% city defense/turn, ignores Walls and Castles

Artillery, Strength 12, +50% city attack, max 25% collateral damage, 80% withdrawal chance, bombard 16% city defense/turn, ignores Walls and Castles
Mobile Artillery, Strength 16, Move 2, +50% city attack, max 25% collateral damage, 85% withdrawal chance, bombard 16% city defense/turn, ignores Walls and Castles


Furthermore, Walls are less resistant to bombardment:
Walls, +50% city defenses, -25% damage to city defenses from bombardment
Castle, +50% city defenses, -25% damage to city defenses from bombardment, +1 trade route, +25% espionage

The Skirmisher and Anti-Tank are reinterpreted as Skirmisher units:
Skirmisher (renamed Javelineer), Strength 3, +100% against Mounted units, targets the weakest unit in a stack
Anti-Tank (renamed Guerrilla), Strength 14, +100% against Armored units, targets the weakest unit in a stack

Comments:
1. Siege units can once again participate in battles and accumulate experience.
2. Siege units have reduced base strength but bonus city attack to accentuate their role in city sieges. They have greatly reduced collateral damage (20-25% down from 50-70%) to retain balance.
3. In the early game, Catapults/Trebuchets conduct collateral damage while Battering Rams/Siege Towers reduce city defenses. Starting with Bombards, Siege units combine both abilities.
4. Suicide-Catapults are history. Siege units will sustain heavy damage in battle (thanks to their reduced strength) but will generally survive (thanks to much higher withdrawal chances.)
5. The heavy damage represents wear and tear and will require repair (that is, a few turns spent healing) before the next battle. This is better for balance, since Siege units can no longer blitz across enemy lines, dealing damage. It is also a better way to model Howard's 'fixed damage per shot' suggestion. The Medic I promotion on Siege Tower further encourages a combined arms strategy.
6. The heavy damage presents an excellent opportunity for Mounted units to flank away Siege units that are not properly defended. This ability does not see much use at the moment, especially by the AI.
7. A limited number of Skirmisher units are introduced. Their purpose is not to harass enemy units before a battle but to ambush enemy units after a battle. I do not know if you can code "targets the weakest unit in a stack."
8. No new unit art is necessary.

Stay tuned for Option B, which transfers collateral damage capabilities from Siege units to a complete new line of Skirmisher units, all converted from existing units.

 

[Azoth]

Proposals on Siege and Skirmisher units, continued.

Option B
Summary
Siege units have zero strength and can be captured. Some Siege units can conduct ranged attacks. Walls are less resistant to bombardment.
A new line of Skirmisher units can conduct collateral damage. Skirmisher units also receive bonus attack damage against a particular unit class and a small withdrawal chance.

Details
Siege units cannot attack. They cannot earn XP and they cannot take promotions. They can be captured like workers but cannot be flanked by Mounted units. They are redesigned as follows:
Battering Ram, cannot attack, bombard 8% city defense/turn, can be captured
Siege Tower, cannot attack, bombard 16% city defense/turn, can be captured

Catapult, can conduct Range 1 attacks, max 20% collateral damage, can be captured
Trebuchet, can conduct Range 1 attacks, max 25% collateral damage, can be captured

Bombard, bombard 12% city defense/turn, ignores Walls and Castles, can conduct Range 1 attacks, max 20% collateral damage, can be captured
Cannon, bombard 12% city defense/turn, ignores Walls and Castles, can conduct Range 1 attacks, max 25% collateral damage, can be captured

Artillery, bombard 16% city defense/turn, ignores Walls and Castles, can conduct Range 2 attacks, max 20% collateral damage, can be captured
Mobile Artillery, bombard 16% city defense/turn, ignores Walls and Castles, can conduct Range 2 attacks, max 25% collateral damage, Move 2, can be captured


Furthermore, Walls are less resistant to bombardment:
Walls, +50% city defenses, -25% damage to city defenses from bombardment
Castle, +50% city defenses, -25% damage to city defenses from bombardment, +1 trade route, +25% espionage


Finally, a new line of Skirmisher units is introduced with collateral damage capability.
Skirmisher (renamed Javelineer), Ancient Era Skirmisher unit, Strength 3, +50% against Archery units, +25% withdrawal chance, max 30% collateral damage
Heavy Javelineer (new unit), Classical Era Skirmisher unit, Strength 4, +50% against Archery units, +30% withdrawal chance, max 30% collateral damage

Crossbowman (name retained), Medieval Era Skirmisher unit, Strength 6, +50% against Melee units, +30% withdrawal chance, max 35% collateral damage
Grenadier (name retained), Renaissance Era Skirmisher unit, Strength 10, +50% against Gunpowder units, +30% withdrawal chance, max 40% collateral damage

Anti-Tank (renamed Partisan), Industrial Era Skirmisher unit, Strength 14, +100% against Armored units, +35% withdrawal chance, max 40% collateral damage
SAM Infantry (renamed Guerrilla), Modern Era Skirmisher unit, Strength 16, +100% against Helicopter units, +35% withdrawal chance, max 45% collateral damage


Comments:
1. Siege units retain ranged attack capability with greatly reduced collateral damage (20-25% down from 50-70%). In exchange, Siege units cannot attack or defend normally but are captured if the other units in their stack are killed. Once again, I am not sure if you can code this.
2. In the early game, Catapults/Trebuchets conduct ranged attacks while Battering Rams/Siege Towers reduce city defenses. Starting with Bombards, Siege units combine both abilities.
3. A full line of Skirmishers units is introduced. They all employ projectile weapons: javelins, crossbows, grenades, bazookas, and surface-to-air missiles. Their purpose is to harass enemy units before a battle, disrupting their formation before the main assault. The game interprets this as collateral damage.
4. The damage from Skirmisher units is slightly higher than Siege units (30-45% compared to 20-25%) to keep them competitive.
5. The remaining Archery units (Archers and Longbowman) are not given collateral damage capability because they are already heavily specialized for city defense.
6. New unit art for the Heavy Javelineer unit is necessary to maintain one new unit per era. If you don't see the need for a Classical Era Skirmisher unit, or simply cannot find the necessary artwork, the unit can be dropped.
7. Skirmishers are renamed Javelineers so that the name 'Skirmisher' can apply to the entire class of units.

 

[Azoth]

Some concluding remarks:

1. I've tried to present two complete, coherent proposals for Siege and Skirmisher units. To a certain extent, we can mix and match ideas from other sources until we're satisfied.
2. However, at some point, we have to make a decision between Option A and Option B: that is, between introducing a new line of Skirmisher units based on existing units; or returning collateral damage capabilities to Siege units.
3. I agree that limiting the number of Siege units or giving them extra unit costs is a poor solution that only masks an underlying imbalance. So I have avoided these options.
4. I also decided not to make use of the "targets certain units first" option. The combat system in BtS encourages combined arms stacks to compensate for rock-paper-scissors vulnerabilities. An entire class of units with target-first capabilities would turn the system on its head.
5. Lastly, I would like to see the name "collateral damage" changed. So far as I know, collateral damage refers to unintentional damage to civilians and their property. So if a Bomber attacked a city and destroyed a Hospital, or if Artillery shelled a fort and killed a Worker, that would be collateral damage. In most video games, "splash damage" refers to damage taken by other enemy targets near the point of impact. I don't know if there is a proper military term for it; but "collateral damage" isn't it.

 

[KaneofEgypt]

Thanks for the unit fix, Xyth, it worked.

 

[Xyth]

Thanks Azoth, some good idea there and a good foundation to get us started on. I haven't got time to comment on it all yet but here's my thoughts on a few aspects. I'll try respond to the rest later and also put my own thoughts together (alongside the feedback so far) in a proposal.

Withdrawal chance for Siege units: while this achieves the goal of having siege units take some damage without being suicidal I feel it requires as much suspension of disbelief as the BTS implementation. Withdrawal chance is used for units that are highly mobile like the Horse Archer; even though it's not intended to mean the same thing in this situation ultimately it gets perceived as such. And it certainly makes no sense for something like a massive stationary Trebuchet to be able to retreat from combat better than considerably more mobile units.

Having said that, I think this a better implementation than suicide siege, but I'd prefer we strive for something more bold and realistic before considering it.

Promotions for Siege Units: we have a fairly important design decision to make here. I did some quick testing and it's not possible to code xp gain for partial damage or bombardment so we can rule those out. Thus, in order for Siege units to gain experience and get promotions they have to be able to completely kill units. In other words, if we want to use non-lethality as a balancing factor then we'll need to scrap siege promotions entirely.

Collateral Damage: I'm not convinced about collateral damage for Skirmisher units, I really feel this should be the role of Archers and Longbowmen in the early eras, Grenadiers and RPG Infantry (my proposal for renamed/redesigned Anti-Tank) in the later eras, and (some) siege weapons throughout.

5. Lastly, I would like to see the name "collateral damage" changed. So far as I know, collateral damage refers to unintentional damage to civilians and their property. So if a Bomber attacked a city and destroyed a Hospital, or if Artillery shelled a fort and killed a Worker, that would be collateral damage. In most video games, "splash damage" refers to damage taken by other enemy targets near the point of impact. I don't know if there is a proper military term for it; but "collateral damage" isn't it.

'Collateral' just means 'parallel' or 'together with'. In the military sense it means unintended additional damage to anything, including enemy forces. It's just in our modern world where most war tends to happen in cities and no longer out in the fields that we've come to associate it with civilian casualties. The word's meaning is changing but I don't think it's inappropriate to use it as it is in the game.

Skirmisher Class: As mentioned I think are possibilities for a Skirmisher Class (if the art allows it) but I don't feel that collateral damage is the role for it. For the time being I'd prefer we focus on Siege and Archery units and look at Skirmishers later.

Defensive Siege Units: One possibility not mentioned in any depth yet is siege units themselves having a counter-siege aspect. In particular I think a Ballista would be an ideal candidate for this and there is art available.

Upkeep: Lets rule out a unit cap for Siege completely, if it has to be capped, it's imbalanced. However I like the idea of Siege units having additional upkeep - this is realistic, helps keep the ratio of siege to other units more sensible, and gives us a little more design room to work with..

 

[Simon_Jester]

Withdrawal chance for Siege units: while this achieves the goal of having siege units take some damage without being suicidal I feel it requires as much suspension of disbelief as the BTS implementation. Withdrawal chance is used for units that are highly mobile like the Horse Archer; even though it's not intended to mean the same thing in this situation ultimately it gets perceived as such. And it certainly makes no sense for something like a massive stationary Trebuchet to be able to retreat from combat better than considerably more mobile units.

Having said that, I think this a better implementation than suicide siege, but I'd prefer we strive for something more bold and realistic before considering it.

I am not sure I agree with your interpretation, Xyth. Withdrawal simply means that your unit can escape before an enemy counterattack overruns it in the event of a lost offensive. That is very much possible with a lot of historical artillery, because you're firing from far enough away that the enemy can't easily capture your position even if your front line crumbles.

There's a reason why "captured guns" (i.e. artillery units overrun by your troops) were the hallmark of decisive military victory from the 1600s up through the World Wars. It was bloody hard to catch the enemy artillery if they didn't want to be caught and fought intelligently.

Promotions for Siege Units: we have a fairly important design decision to make here. I did some quick testing and it's not possible to code xp gain for partial damage or bombardment so we can rule those out. Thus, in order for Siege units to gain experience and get promotions they have to be able to completely kill units. In other words, if we want to use non-lethality as a balancing factor then we'll need to scrap siege promotions entirely.

That, or make them balanced so that they are effective when Barracks XP and civic XP is factored in- we can't count on any one artillery unit getting 20 XP, but we can count on lots of 'em with 3 or 5 XP each. Give them promotions that make that worthwhile, if you ask me. It gives you a bit more customizability and tactical flexibility, but does require you to think a little about things like how the Accuracy promotion works.

Collateral Damage: I'm not convinced about collateral damage for Skirmisher units, I really feel this should be the role of Archers and Longbowmen in the early eras, Grenadiers and RPG Infantry (my proposal for renamed/redesigned Anti-Tank) in the later eras, and (some) siege weapons throughout.

Hmm.

As to "RPG infantry," I don't like that because "RPG" is not a generic term the way "SAM" is. SAM means "surface to air missile," and applies equally well to everyone else's weapons. "RPG" refers specifically to Soviet-made antitank rockets, and not all antitank rockets use the same design principles as the RPG either.

So while "SAM infantry" is culture-nonspecific, "RPG infantry" is not. While "Anti-Tank" or the like may be unpleasantly generic, it's at least neutral.

Defensive Siege Units: One possibility not mentioned in any depth yet is siege units themselves having a counter-siege aspect. In particular I think a Ballista would be an ideal candidate for this and there is art available.

Interesting if we can make the AI use it.

 

[Xyth]

I am not sure I agree with your interpretation, Xyth. Withdrawal simply means that your unit can escape before an enemy counterattack overruns it in the event of a lost offensive. That is very much possible with a lot of historical artillery, because you're firing from far enough away that the enemy can't easily capture your position even if your front line crumbles.

Hmm I didn't think of it this way, that makes sense at least for post-gunpowder artillery. I still think it doesn't work for earlier siege units though. Trebuchets weren't mobile at all, they needed to be assembled at the site of the siege before they could be used (pity we can't emulate this like in Civ5). They'd require disassembly and packing to escape.

That, or make them balanced so that they are effective when Barracks XP and civic XP is factored in- we can't count on any one artillery unit getting 20 XP, but we can count on lots of 'em with 3 or 5 XP each. Give them promotions that make that worthwhile, if you ask me. It gives you a bit more customizability and tactical flexibility, but does require you to think a little about things like how the Accuracy promotion works.

"RPG" refers specifically to Soviet-made antitank rockets, and not all antitank rockets use the same design principles as the RPG either.

So while "SAM infantry" is culture-nonspecific, "RPG infantry" is not. While "Anti-Tank" or the like may be unpleasantly generic, it's at least neutral.

Ah I didn't realize that. Nevermind then.

Interesting if we can make the AI use it.

I'm pretty sure we can with the right selection of stats and UnitAI scripts. I think it would be the perfect niche for the Ballista though I'm not sure what the gunpowder-era equivalent would be. Any suggestions?

 

[Xyth]

Okay, now responding to the rest of Azoth's proposals. Overall I think Option A is the better of the two, despite it's removal of ranged attacks.

Furthermore, Walls are less resistant to bombardment:

This seems a reasonable change. I'm curious though, what are the pros/cons of doing this over boosting the bombard strength of each siege unit (e.g 8% ---> 10%, 16% ---> 20%)

Siege units have reduced base strength but bonus city attack to accentuate their role in city sieges.

I think this is a good idea. I would possibly change the Bombard to Strength 5, +100% City Attack. Like the Trebuchet, Bombards seem very unsuited to battle beyond city sieges.

They have greatly reduced collateral damage (20-25% down from 50-70%) to retain balance.

There are actually 3 variables we can tweak here. We can adjust the % limit of collateral damage and we can adjust the maximum number of units affected by collateral damage. The latter doesn't show in the pedia or tooltips, though I'll see if I can add it. The defaults for it are 5 (Skirmisher, Tank, Battleship, Missile Cruiser, Bomber) 6 (Catapult, Trebuchet, Modern Armour, Stealth Bomber), 7 (Bombard and Cannon), 8 (Artillery, Mobile Artillery).

Finally we can adjust the amount of collateral damage itself, as a percentage of unit strength. The Battleship, for example, does collateral damage at 50% of it's combat strength. All the Artillery units do 100% of their combat strength.

In the early game, Catapults/Trebuchets conduct collateral damage while Battering Rams/Siege Towers reduce city defenses. Starting with Bombards, Siege units combine both abilities.

This was always my plan. I reverted it at some point and I honestly cannot remember why.

Suicide-Catapults are history. Siege units will sustain heavy damage in battle (thanks to their reduced strength) but will generally survive (thanks to much higher withdrawal chances.)

The heavy damage represents wear and tear and will require repair (that is, a few turns spent healing) before the next battle. This is better for balance, since Siege units can no longer blitz across enemy lines, dealing damage. It is also a better way to model Howard's 'fixed damage per shot' suggestion.

I like the result, I'd just prefer another method of reaching it. If we can do it via ranged attacks then we should try, if not then we have a system that is much better than what's currently in game to fall back on.

The Medic I promotion on Siege Tower further encourages a combined arms strategy.

A random idea I had a while back but never tested or explored further was making the Ram and Tower units act a bit like Great Generals; they'd not be used in actual combat but would instead attach to units and give them free promotions. I was also considering a Supply Train unit that worked along similar lines.

I don't know if this is worth reconsidering or not, let me know what you think.

The heavy damage presents an excellent opportunity for Mounted units to flank away Siege units that are not properly defended. This ability does not see much use at the moment, especially by the AI.

Looks like most mounted units are missing the UnitAI script that would encourage the AI to keep some in cities to counter attacking units... that's quite the oversight by the designers of BTS. So maybe we can encourage flank attacks more often.

I do not know if you can code "targets the weakest unit in a stack.

I cannot.

Siege units have zero strength

Note that it's possible to give units different combat strength and ranged strength (though it would require some pedia/tooltip tweaks to display properly)

In exchange, Siege units cannot attack or defend normally but are captured if the other units in their stack are killed. Once again, I am not sure if you can code this.

I haven't tested it yet but I'm pretty sure we can make siege units able to be captured.

A full line of Skirmishers units is introduced. They all employ projectile weapons: javelins, crossbows, grenades, bazookas, and surface-to-air missiles. Their purpose is to harass enemy units before a battle, disrupting their formation before the main assault. The game interprets this as collateral damage.

If we do go down the route of adding a full Skirmisher class I'd prefer them to be about harrying specific targets, escaping easily, but dying swiftly if cornered.

The remaining Archery units (Archers and Longbowman) are not given collateral damage capability because they are already heavily specialized for city defense.

To me a great hail of arrows falling on an army denotes collateral damage more than almost any other type of attack. Archery units are specialized for city defense but I'd like to see them out in the field and even attacking cities too. Perhaps we should split their city defense role with Spear/Pikeman.

New unit art for the Heavy Javelineer unit is necessary to maintain one new unit per era. If you don't see the need for a Classical Era Skirmisher unit, or simply cannot find the necessary artwork, the unit can be dropped.
7. Skirmishers are renamed Javelineers so that the name 'Skirmisher' can apply to the entire class of units.

It *might* be possible to introduce Slingers/Peltasts as a new ancient/classical alternative to Javelineers. Don't count on it for the moment though, I'll do a proper assessment once we've got Siege units sorted.

 

[Simon_Jester]

Hmm I didn't think of it this way, that makes sense at least for post-gunpowder artillery. I still think it doesn't work for earlier siege units though. Trebuchets weren't mobile at all, they needed to be assembled at the site of the siege before they could be used (pity we can't emulate this like in Civ5). They'd require disassembly and packing to escape.

Trebuchets were also useless in a field battle, for exactly that reason, whereas the Romans had mechanical artillery (a general term for pre-gunpowder ranged siege weapons) of smaller size that worked in the field... and would have basically that same advantage of permitting a defeated army to hitch up the artillery and haul it away after the battle as long as they aren't totally routed.

Vanilla actually has, in my opinion, a good way of resolving this- Trebuchets are weak except when attacking cities. We might want to do the same thing- their being able to do ahistorical "hit and run" operations matters less if they can't hit worth a damn. It may not be perfect historical emulation, but frankly on the very zoomed-out strategic scale of the game, it's about as good as we're going to get. We're trying to do a strategy simulator, not Total War Medieval here.

By the way, what did you think of me writing this?

That, or make them balanced so that they are effective when Barracks XP and civic XP is factored in- we can't count on any one artillery unit getting 20 XP, but we can count on lots of 'em with 3 or 5 XP each. Give them promotions that make that worthwhile, if you ask me. It gives you a bit more customizability and tactical flexibility, but does require you to think a little about things like how the Accuracy promotion works.

I'm pretty sure we can with the right selection of stats and UnitAI scripts. I think it would be the perfect niche for the Ballista though I'm not sure what the gunpowder-era equivalent would be. Any suggestions?

During the gunpowder age most artillery duels were symmetrical- roughly similar guns on each side. If you want dedicated counterbattery units that kill siege engines I'll see if I can think of something, but it's a bit tricky.

This seems a reasonable change. I'm curious though, what are the pros/cons of doing this over boosting the bombard strength of each siege unit (e.g 8% ---> 10%, 16% ---> 20%)

Because that becomes unbalanced in the post-gunpowder era. Either individual artillery units can reduce city defenses by 40% per turn or something, at which point city defense becomes practically irrelevant, or you wind up with a perverse situation where the best way to reduce the defenses of a modern city protected by dug-in machine battalions is to use a siege tower

I think this is a good idea. I would possibly change the Bombard to Strength 5, +100% City Attack. Like the Trebuchet, Bombards seem very unsuited to battle beyond city sieges.

17th century artillery was already seeing use in the open field- and was routinely breaking the pike/arquebus and pike/musket armies of the period. It evolved fairly seamlessly into the classical Napoleonic guns of the 18th century.

It's only when you go back to the 1400s and 1500s that artillery becomes too clumsy for field battles, and that really doesn't represent the gunpowder era well. When do we make the transfer between Bombards and Cannon again? Is it at a tech level which more corresponds to "late medieval" or to "Mid-renaissance?"

There are actually 3 variables we can tweak here. We can adjust the % limit of collateral damage and we can adjust the maximum number of units affected by collateral damage. The latter doesn't show in the pedia or tooltips, though I'll see if I can add it. The defaults for it are 5 (Skirmisher, Tank, Battleship, Missile Cruiser, Bomber) 6 (Catapult, Trebuchet, Modern Armour, Stealth Bomber), 7 (Bombard and Cannon), 8 (Artillery, Mobile Artillery).

Finally we can adjust the amount of collateral damage itself, as a percentage of unit strength. The Battleship, for example, does collateral damage at 50% of it's combat strength. All the Artillery units do 100% of their combat strength.

Oooh. Interesting. We need to apply some thought to this.

Frankly, in general early mechanical artillery should do collateral damage to few units, while the max number of units starts going up significantly post-gunpowder. One stealth bomber can cripple whole armies, even without nuclear weapons, by targeting the command post coordinating that army, for example.

Note that it's possible to give units different combat strength and ranged strength (though it would require some pedia/tooltip tweaks to display properly)

Oooh. That would solve a lot of problems- if artillery is more effective used in a direct attack role, or it takes a prohibitively large force to destroy enemy units with ranged attacks, the balance issue becomes less important.

I haven't tested it yet but I'm pretty sure we can make siege units able to be captured.

Captured guns, bygod!

[puts on monocle and whatnot of Victorian infantry officer]

 

[Howard Mahler]

Archery units are currently quite useful.
Players and AI build a lot of archery units.
There is no need to strengthen them.
If you add collateral damage, then you need to take away all of those things that currently make archers valuable.

We have to remember that each tile is about 200 miles across.
Combat represents a very large battle or a series of large battles taking place somewhere in this space.
In early times, think of tens of thousands or even hundreds of thousands of people spread over several square miles.

In this framework, it is unclear what collateral damage is intended to represent for any early unit.

The masses of arrows flying are what is causing the basic damage from an archery unit. One large group of archers firing at a large group of enemy.

I do not see collateral damage from archery units as adding either to game play or realism.

Collateral damage was introduced as a game mechanism to try to counter "Stacks of Doom." I suspect we can get by without collateral damage at least in the early game. One could also increase the cost of building and/or maintaining military units. This would cut down on the size of armies.

 

[Howard Mahler]

It is unfortunate that the AI (as programmed for BTS) does not seem to understand ranged attacks. However, given that fact, I lean towards getting rid of ranged attacks.

In contrast, the AI seems to do OK with units that bombard cities.

The AI also seems to understand "suicide" units that cause collateral damage.(See BTS.) Skirmishers do collateral daamge and have a withdrawal chance, and the AI seems to be able to handle them. (This has nothing to with whether current Skirmishers should remain.)

So it seems there are at least three choices:
1. No collateral damage units.
(Note that cavalry would still get flanking attacks.
Bombers and Battleships could still do collateral damage.)
2. Collateral damage units with withdrawal chances.
3. Collateral damage units similar to BTS.

I could live with choice 1, at least until the late game.
Choice 2 can be made to work.
Choice 3 works in BTS, although as implemented there it has "realism" problems.

 

[Azoth]

Excellent discussion, everyone. Now for some responses:

Overall I think Option A is the better of the two, despite it's removal of ranged attacks.

I agree.

I am not sure I agree with your interpretation, Xyth. Withdrawal simply means that your unit can escape before an enemy counterattack overruns it in the event of a lost offensive. That is very much possible with a lot of historical artillery, because you're firing from far enough away that the enemy can't easily capture your position even if your front line crumbles.

Hmm I didn't think of it this way, that makes sense at least for post-gunpowder artillery. I still think it doesn't work for earlier siege units though. Trebuchets weren't mobile at all, they needed to be assembled at the site of the siege before they could be used (pity we can't emulate this like in Civ5). They'd require disassembly and packing to escape.

I interpret withdrawal chances as simply "the ability to disengage from battle." As I see it, that initiative is entirely in the hands of the besieging army: they can call an end to the assault at a time of their choosing. The besieged army, by contrast, has no means of escape: they must defend their city and hope for the best.

So the issue here is not whether your artillery will ultimately evade capture. (The enemy can only counterattack on the next turn; but after a failed siege, your forces will be overrun.) Rather the issue is whether, during the actual siege, your artillery will keep firing until every last piece is destroyed and every engineer slain. I say that your infantry will move in as soon as the enemy is sufficiently weakened and your artillery will live to fight another day. (No Suicide-Catapults here.) That's why high withdrawal chances make sense for Siege units.

Promotions for Siege Units: we have a fairly important design decision to make here. I did some quick testing and it's not possible to code xp gain for partial damage or bombardment so we can rule those out. Thus, in order for Siege units to gain experience and get promotions they have to be able to completely kill units. In other words, if we want to use non-lethality as a balancing factor then we'll need to scrap siege promotions entirely.

That, or make them balanced so that they are effective when Barracks XP and civic XP is factored in- we can't count on any one artillery unit getting 20 XP, but we can count on lots of 'em with 3 or 5 XP each. Give them promotions that make that worthwhile, if you ask me. It gives you a bit more customizability and tactical flexibility, but does require you to think a little about things like how the Accuracy promotion works.

Note that you do gain experience for a successful withdrawal.
So the real decision is between:

• Siege units that can attack directly; and
• Siege units that only attack indirectly, via ranged attacks and city bombardment.

Most promotions (City Raider, Drill) do not affect ranged attacks or city bombardment. Frankly, I'm not even sure if Barrage promotions increase ranged attack damage; they might only affect collateral damage. In that case, we may as well scrap siege promotions entirely; the Accuracy promotion isn't worth keeping on its own.

I would possibly change the Bombard to Strength 5, +100% City Attack. Like the Trebuchet, Bombards seem very unsuited to battle beyond city sieges. [...] There are actually 3 variables we can tweak here. We can adjust the % limit of collateral damage and we can adjust the maximum number of units affected by collateral damage. [...] Finally we can adjust the amount of collateral damage itself, as a percentage of unit strength.

Very interesting. Lots of possibilities here.
As soon as we decide whether Siege units will have collateral damage or ranged attacks, we can discuss the details.
It would be a good idea to include the information in the 'pedia, as you suggest.

Looks like most mounted units are missing the UnitAI script that would encourage the AI to keep some in cities to counter attacking units... that's quite the oversight by the designers of BTS. So maybe we can encourage flank attacks more often.

It might not be that easy. Flank Attacks succeed only when a Mounted unit scores a kill against a stack containing Siege units. (I'm not sure if a withdrawal counts.) You can discourage such attacks, or at least reduce their chances of success, simply by protecting your Siege units with Spearmen and Pikemen. (Not to mention, Mounted units are terrible on defence, so there's no other reason to keep them in cities.)

I haven't tested it yet but I'm pretty sure we can make siege units able to be captured.

Would that require Siege units to have zero strength?
Either way, we'd have to remove Flank Attacks on Mounted units.
There's no point in flanking away Siege units you hope to capture.

I'm curious though, what are the pros/cons of doing this over boosting the bombard strength of each siege unit (e.g 8% ---> 10%, 16% ---> 20%)

Because that becomes unbalanced in the post-gunpowder era. Either individual artillery units can reduce city defenses by 40% per turn or something, at which point city defense becomes practically irrelevant, or you wind up with a perverse situation where the best way to reduce the defenses of a modern city protected by dug-in machine battalions is to use a siege tower

Not only that, higher bombard strength would be too powerful against cities without Walls and Castles. As it stands, the standard response to an incoming AI stack is to rush Walls in the target city; in most cases, that leaves you enough time to round up units from nearby cities and repel the invasion. It's a little too exploitative for my taste; you can easily bait AI Siege units by having them waste precious turn bombarding your super-strong Walls.

Defensive Siege Units: One possibility not mentioned in any depth yet is siege units themselves having a counter-siege aspect. In particular I think a Ballista would be an ideal candidate for this and there is art available.

What would the mechanics look like?
The best bonus for counter-siege units is immunity to collateral damage.
(Horse Archers already have an attack bonus against Siege units, on top of the Flanking Attack they share with all Mounted units; and I don't think a defence bonus against Siege units is the way to go.)
In that case, Ballistae with immunity to collateral damage have a natural Industrial-Era counterpart: the Machine Gun.

Upkeep: Lets rule out a unit cap for Siege completely, if it has to be capped, it's imbalanced. However I like the idea of Siege units having additional upkeep - this is realistic, helps keep the ratio of siege to other units more sensible, and gives us a little more design room to work with..

Maybe. I still think extra unit costs are less than ideal. In principle, the only cost to building a particular unit, building, or improvement should be the opportunity cost of not building something else. For example, if you construct a Barracks in your second city but train most of your units elsewhere, your only loss is the opportunity cost of constructing a more useful building. Likewise, if you build a Road that is never used, your only loss is the worker turns that could have been better spent elsewhere. If the Barracks or the Road require gold to maintain, as they do in Civilization V, then you need to make a cost-benefit analysis every time you build one. In the case of Siege units, players would be encouraged to train them on the last possible turn before war, and disband them as soon as their goals were accomplished. They would see a gold piece wasted for every turn a Siege unit wasn't involved in combat. I think we should avoid such dynamics as much as possible. (Granted, your army will still be assessed for general unit costs; but those are more bearable because they are proportional to the size of your army, and do not fall upon any units in particular.)

If we do go down the route of adding a full Skirmisher class I'd prefer them to be about harrying specific targets, escaping easily, but dying swiftly if cornered. [...] To me a great hail of arrows falling on an army denotes collateral damage more than almost any other type of attack. Archery units are specialized for city defense but I'd like to see them out in the field and even attacking cities too. Perhaps we should split their city defense role with Spear/Pikeman.

I have to agree with Howard here. Archers/Longbowmen and Spearmen/Pikemen are already specialized for city defence and anti-cavalry. They are very effective in their respective roles and should be left alone. In fact, I suggested that Crossbowmen, Grenadiers, and Anti-Tanks should be reworked Skirmisher units precisely because I felt they lacked a clear purpose. And when it comes down to it: given the scale of the battlefield, a burst of cannon or a barrage of stones could conceivably count as collateral damage. A hail of arrows is merely a first strike chance.

 

[Simon_Jester]

Note that you do gain experience for a successful withdrawal.
So the real decision is between:

• Siege units that can attack directly; and
• Siege units that only attack indirectly, via ranged attacks and city bombardment.

Most promotions (City Raider, Drill) do not affect ranged attacks or city bombardment. Frankly, I'm not even sure if Barrage promotions increase ranged attack damage; they might only affect collateral damage. In that case, we may as well scrap siege promotions entirely; the Accuracy promotion isn't worth keeping on its own.

I like direct-attack siege units with high withdrawal and collateral damage. That's almost how BTS does it; the only catch is the withdrawal odds not being so great.

Would that require Siege units to have zero strength?
Either way, we'd have to remove Flank Attacks on Mounted units.
There's no point in flanking away Siege units you hope to capture.

I disagree- ideally you want to capture artillery, but that doesn't mean you'd rather not simply destroy it if that's easier- say, if you're outnumbered and want to neutralize the enemy's siege ability.

Not only that, higher bombard strength would be too powerful against cities without Walls and Castles. As it stands, the standard response to an incoming AI stack is to rush Walls in the target city; in most cases, that leaves you enough time to round up units from nearby cities and repel the invasion. It's a little too exploitative for my taste; you can easily bait AI Siege units by having them waste precious turn bombarding your super-strong Walls.

Yeah, that's kind of my point too- I was thinking in terms of post-gunpowder when walls and castles become obsolete and are no longer buildable: how do you defend your cities against 24%/turn bombarding Siege Towers clearing the way for the tanks when you can't build castles?

What would the mechanics look like?
The best bonus for counter-siege units is immunity to collateral damage.
(Horse Archers already have an attack bonus against Siege units, on top of the Flanking Attack they share with all Mounted units; and I don't think a defence bonus against Siege units is the way to go.)
In that case, Ballistae with immunity to collateral damage have a natural Industrial-Era counterpart: the Machine Gun.

Hmmm, sort of. That might work.

I have to agree with Howard here. Archers/Longbowmen and Spearmen/Pikemen are already specialized for city defence and anti-cavalry. They are very effective in their respective roles and should be left alone. In fact, I suggested that Crossbowmen, Grenadiers, and Anti-Tanks should be reworked Skirmisher units precisely because I felt they lacked a clear purpose. And when it comes down to it: given the scale of the battlefield, a burst of cannon or a barrage of stones could conceivably count as collateral damage. A hail of arrows is merely a first strike chance.

Given their relative prevalence, arguably crossbowmen make more sense as the designated medieval city defender than longbowmen- while improved bows in the middle ages were common, many of the basic types (composite, recurve) were already in play in ancient/classical times. Whereas the crossbow is uniquely medieval, and was used throughout Eurasia wherever infantry combat was common.

Eh, I dunno.

 

[Xyth]

Haven't got time to respond to everything atm, here's as much as I can fit in before I need to leave for work:

Vanilla actually has, in my opinion, a good way of resolving this- Trebuchets are weak except when attacking cities.

Azoth has proposed we do this to varying degrees for most siege units. I think it makes sense for everything prior to the Cannon.

That, or make them balanced so that they are effective when Barracks XP and civic XP is factored in- we can't count on any one artillery unit getting 20 XP, but we can count on lots of 'em with 3 or 5 XP each. Give them promotions that make that worthwhile, if you ask me. It gives you a bit more customizability and tactical flexibility, but does require you to think a little about things like how the Accuracy promotion works.

It does sound like there won't be many promotions available to siege units, even if they can earn xp via withdrawals so we might as well make them enticing ones.

Because that becomes unbalanced in the post-gunpowder era. Either individual artillery units can reduce city defenses by 40% per turn or something, at which point city defense becomes practically irrelevant, or you wind up with a perverse situation where the best way to reduce the defenses of a modern city protected by dug-in machine battalions is to use a siege tower

Not only that, higher bombard strength would be too powerful against cities without Walls and Castles. As it stands, the standard response to an incoming AI stack is to rush Walls in the target city; in most cases, that leaves you enough time to round up units from nearby cities and repel the invasion. It's a little too exploitative for my taste; you can easily bait AI Siege units by having them waste precious turn bombarding your super-strong Walls.

Good points, wall reduction seems a sensible thing to do.

It's only when you go back to the 1400s and 1500s that artillery becomes too clumsy for field battles, and that really doesn't represent the gunpowder era well. When do we make the transfer between Bombards and Cannon again? Is it at a tech level which more corresponds to "late medieval" or to "Mid-renaissance?"

The Bombard is available with Gunpowder so it's late medieval/early renaissance.


Frankly, in general early mechanical artillery should do collateral damage to few units, while the max number of units starts going up significantly post-gunpowder. One stealth bomber can cripple whole armies, even without nuclear weapons, by targeting the command post coordinating that army, for example.

Oooh. That would solve a lot of problems- if artillery is more effective used in a direct attack role, or it takes a prohibitively large force to destroy enemy units with ranged attacks, the balance issue becomes less important.

My testing seems to indicate that the AI really doesn't know what to do when a unit can do both direct and ranged attacks. If ranged attack strength is lower it will always use the direct attack instead. It can't understand the tactical advantage of a ranged attack. So unfortunately we have to rule this out and have all units do direct attacks or ranged attacks, and not both. Bombardment is handled differently and is thus not a problem.

Captured guns, bygod!

Would that require Siege units to have zero strength?

Nope, we can make any unit capturable, regardless of combat strength. They just have to be defeated in direct combat.

Very interesting. Lots of possibilities here.
As soon as we decide whether Siege units will have collateral damage or ranged attacks, we can discuss the details.

I don't see it as a choice between collateral and ranged, I see it as a choice between ranged (plus counter mechanics) and withdrawal. So yes, Siege units will definitely do some collateral damage.

It would be a good idea to include the information in the 'pedia, as you suggest.

Hopefully I can figure out how. Worst case scenario I can add entries for each unit with fixed values.

It might not be that easy. Flank Attacks succeed only when a Mounted unit scores a kill against a stack containing Siege units. (I'm not sure if a withdrawal counts.) You can discourage such attacks, or at least reduce their chances of success, simply by protecting your Siege units with Spearmen and Pikemen. (Not to mention, Mounted units are terrible on defence, so there's no other reason to keep them in cities.)

Almost makes me tempted to give flanking attacks to another class, perhaps Skirmishers? Flanking really is a mounted concept though so probably not.

Either way, we'd have to remove Flank Attacks on Mounted units.
There's no point in flanking away Siege units you hope to capture.

I disagree- ideally you want to capture artillery, but that doesn't mean you'd rather not simply destroy it if that's easier- say, if you're outnumbered and want to neutralize the enemy's siege ability.

I don't see any reason to remove flank attacks. Gives the player a choice.

What would the mechanics look like?
The best bonus for counter-siege units is immunity to collateral damage.

Assuming siege weapons have ranged attacks, the Ballista (also with ranged attacks) would always target Siege weapons first in a stack. In other words, you'd defend against range attack siege weapons with Ballista + collateral damage from defenders (thus why I was talking about giving Archery units collateral damage as well). Active defense.

In that case, Ballistae with immunity to collateral damage have a natural Industrial-Era counterpart: the Machine Gun.

I like this.


Out of time, more later.

 

[Xyth]

It is unfortunate that the AI (as programmed for BTS) does not seem to understand ranged attacks. However, given that fact, I lean towards getting rid of ranged attacks.

It does understand ranged attacks, it's just that it doesn't know how to counter them effectively at the moment. We can address this by making siege units themselves able to counter other siege units. Removing their immunity to collateral damage would go a long way towards balancing things.

The AI also seems to understand "suicide" units that cause collateral damage.(See BTS.) Skirmishers do collateral daamge and have a withdrawal chance, and the AI seems to be able to handle them. (This has nothing to with whether current Skirmishers should remain.)

There should be no difference between collateral via direct attack and collateral via ranged attack as far as the AI is concerned. The AI does tend to not use collateral attacks until city defenses have been fully bombarded though.

I interpret withdrawal chances as simply "the ability to disengage from battle." As I see it, that initiative is entirely in the hands of the besieging army: they can call an end to the assault at a time of their choosing. The besieged army, by contrast, has no means of escape: they must defend their city and hope for the best.

The problem is that we all seem to interpret it differently. None of us are wrong or right, it's a bit of a vague concept. In isolation it's easily definable but when you start comparing it across noticeably different unit classes it gets messy. It's just not intuitive to how people expect ranged siege weapons to behave. Let me explain:

To attack with a unit you move it into the enemy position, there is a battle and one of the units is defeated or the attacker retreats. This makes perfect sense for most units, it feel intuitive. But not for ranged siege weapons which are supposed to be immobile. In BTS this feels ridiculous because it's as if you just rolled your trebuchet into the enemy lines (or at least out front of your lines) and started firing away until the enemy eventually destroyed it. This is where the 'suicide siege' moniker comes from. Ranged siege feel like they should behave differently to other units but they don't.

By adding a withdrawal chance the effect is the roughly the same except that the trebuchet seems to move back as well as forward. We, as the designers, know that this isn't the case, it's being used to emulate immobile attacks from range. But we're asking the player to make an interpretation that just isn't intuitive and one that even we don't have absolute consensus on; a trebuchet in reality attacks and defends very different to a Horse Archer or a Javelineer - yet the game mechanic is the same. We're addressing balance but we're not addressing the suspension of disbelief. We don't have to address it, but we should try.

This is why I want to strive for ranged combat. It will be harder to balance but I believe it can be done. PAE did it, so can we. I'm working on a rough proposal, an Option C, to give everyone a better idea of how it might look.

Archery units are currently quite useful.
Players and AI build a lot of archery units.
There is no need to strengthen them.
If you add collateral damage, then you need to take away all of those things that currently make archers valuable.

I have to agree with Howard here. Archers/Longbowmen and Spearmen/Pikemen are already specialized for city defence and anti-cavalry. They are very effective in their respective roles and should be left alone. In fact, I suggested that Crossbowmen, Grenadiers, and Anti-Tanks should be reworked Skirmisher units precisely because I felt they lacked a clear purpose. And when it comes down to it: given the scale of the battlefield, a burst of cannon or a barrage of stones could conceivably count as collateral damage. A hail of arrows is merely a first strike chance.

Yeah I agree here, no point fixing what isn't broken. However, Simon has just identified and solved the issue for me:

Given their relative prevalence, arguably crossbowmen make more sense as the designated medieval city defender than longbowmen- while improved bows in the middle ages were common, many of the basic types (composite, recurve) were already in play in ancient/classical times. Whereas the crossbow is uniquely medieval, and was used throughout Eurasia wherever infantry combat was common.

Crossbowman should indeed be the medieval city defender and not Longbowmen. Longbowmen should be an offensive units, harrying armies out in the field and possibly even assisting city sieges. In other words, they make much more sense as the Medieval equivalent of the Skirmisher/Javelineer. To use a longbow (or other powerful type of bow) required a lot of strength, training and skill. Crossbows on the other hand were deadly with minimal training, the ideal weapon for equipping the peasantry.

The Crossbowman can get the Longbowman's stats and the Longbowman can be redesigned more along the lines of the current Skirmisher with some collateral damage and withdrawal chance. The Archer can stay as is.