If you split your army into many stacks and advance as a front the enemy will tear them apart by attacking the stacks that are in poor tactical positions. In order to prevent an enemy breach you'll have to have a continuous line of stacks, and that means some of them will have to be on flat unforested land. Also, having fewer units in a stack increases the chance that the whole stack will be killed as a result of being overwhelmed.
Even if your front is impenetrable there's the issue of caster usefulness. Depending on what spheres you have, the impact of your strategy will vary. Summoning undead from behind the lines works just fine, but it's hard to rust a foe's weapons from two squares away. Maelstrom would be worthless because you'd cripple 5 of your own stacks trying to wear down a city.
And finally, if someone was able to use the front line strategy and make it work then what do they need the guardsmen for anyway? I guess invisible assassins would still be a threat, but most opponents aren't going to be able to crank those out.
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The Guardsman promotion takes a fair bit of work to get. Combat I - IV + Guardsman means it's a L6 unit. That may be trivial for a hero, but other units have to survive a fair bit of combat to reach that point. Compare that to the difficulty of getting a Marksman: build it. Yeah, a unit with Guardsman is going to be much stronger than a newly built unit with Marksman, but the potential supply of Marksmen will always be greater than the potential supply of Guardsmen, once the ability to built Marksmen as been researched. If you flood your opponent with assassins (in an organized, strategic way rather than as lambs-to-the-slaughter) the Guardsmen will eventually all be dead. As it stands now, because of their increased chance to defend any stack they are in, they are easy to eliminate with normal units. This greatly reduces the chance that they will be able to serve their intended function.
The opportunity to serve that intended function comes at a cost. You paid for it by purchasing the promotion, as well as the opportunity cost of not taking better promotions. That same L6 unit, for example, could have had Combat I, Shock I, C II & III, and S II. Or, it could have CI, Cover, and City Raider I - III. Both of those promotion paths are very useful and arguably better than the Guardsman path, unless you happen to need a unit that can protect a vulnerable but valuable weak unit. I think it is appropriate for units that have purchased Guardsman to have a little bit of hope that they will actually serve to protect against a Marksman.
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I'd like to see Guardsman changed to:
- Decreased chance to defend the stack
- Guards against enemy Marksman units
... meaning that if the attacker has
Marksman then a unit with
Guardsman will always be selected first to defend the stack (no matter how injured it is). If the attacker doesn't have
Marksman then the
Guardsman will only defend the stack if all the units in the stack have a decreased chance to defend (ie only Guardsmen and squishies are left).
The result of this change would be:
- Guardsman will be protected from casual attackers until all of the non-squishy units have been defeated or severely wounded
- Guardsman will defend squishy units against Marksmen
- Marksmen will have the opportunity to bypass non-Guardsman defenders and overwhelm the Guardsmen, rendering the weak targets vulnerable
This allows the Guardsmen to guard, and the Marksmen to still have a chance to take out vulnerable targets in a large stack.
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This change would be problematic for the Elohim, because of their Guardsman trait. Recon and mounted units would be left defending the stack while archers hid behind them. I propose that all Elohim units that do not currently receive the Guardsman promotion should receive a promotion that reduces their chance to defend the stack. This would allow those units to properly be defended by the Elohim units that are probably better defenders (ie archers).