Regarding Tribal Forts...
I've noticed that defeating one might now grant a slave, which turns into a worker if you don't run slavery. Nice and logical.
However, it does make an exploit with the Fort even more lucrative. Here it is:
Your early warrior has about 76% chance of defeating the Fort.
How? You ask. It's because the game has you win the first ever combat you have with a barbarian unit. I'm not sure how far back this behavior goes, possibly as far as Vanilla, and maybe it can't be changed. The reasoning has probably been that you won't get blown out of the game in the first few turns by losing to a random animal, or a goody hut barbarian popped by a neighboring civ. It's not a 100% chance, and I suspect this is because of first strikes. Those are handled normally, and the fort can actually kill your unit with them. But the actual combat, your puny warrior defeats the barbarian town every time.
As long as you haven't "wasted" your first combat somewhere you can now do one of the following depending on which civ you play:
- Defeat random fort with no strategic purpose. Get a +10 XP warrior, and possibly a worker.
- Defeat a solitary fort to gain access to a square, with Europe you now have passage north of the alps below the Netherlands for longer than usual, for example.
- Defeat a city defended by a solitary fort, like Riga, or the town north of Jerusalem, raze it, or better yet, capture it once it's grown size 2 but doesn't yet have another defender built. The AI sometimes stumbles upon this, with Israel having 2 cities, or the Poles controlling Riga, which is how I noticed this thing in the first place. You can also capture the archer-defended Illyria this way immediately.
Like I said, it doesn't work 100% of the time, but the payoff is well worth the risk, and frankly I load and try again (after rng reseeds) until I succeed. It offers rather interesting strategic options. (And the AI does benefit from it occasionally, because the odds are calculated properly.)
As soon as you fight a single combat against a barb though, the benefit is gone.
@kiwi_lifter: Open TR_Unique_Units_CIV4UnitInfos in Mods/Realism/Assets/XML/Units in notepad. Ctrl-F to find UNIT_BARBARIAN_FORT.
Also, my description of the exploit above should explain how the AI came to possess it with a few militia, as you say. Still, a solitary barbarian fort *can* be defeated by a stack of swordsmen alone. It just has to be a large stack. And you need to be lucky, well, not unlucky. Proof: I once cleared the whole of Australia (the Aborigines have forts too) with Austronesia by mid-medieval. Although it really only starts becoming "easy" after you have access to Pikemen. Single unit stacks of your heaviest hitters work best (obviously drop the defenses to 0 first), the forts fart in the general direction of combined arms stacks. 10 units minimum for 1 fort with no other defenders. Remember to bring enough to finish the whole town in a single turn, the forts heal immediately, and get promotions to boot from a failed assault. Regular defenders like warriors can be a nightmare due to sheer numbers, for if the fort is finally damaged heavily, but doesn't get destroyed, it might hide behind those, and you really really need to win on the first turn of attacking (not counting bombardment).
It might take 5 or even 10 units before the fort has even a single dent, but the rng has to cave in eventually, and the chances for the fort to not get damage from a single attacker start dropping dramatically once it has that single dent.
Towns with 3 forts... ye gods! I've sent stacks of 50 units against those to be sure. Nuking from orbit is best.
