I found this to also be the case...I have never had as many armies as I have at once with the TK. They are definately a snowball faction...especially once you pass up basic units for Ushabti/Tomb Guards.
Full armies of Ushabti are hilarious to watch.
I kinda prefer Stalkers myself. They seem tankier for some reason. They're also bigger, heh.
They have some kind of ranged attack but I can't figure out what are the specific conditions to get them to fire. Sometimes they shoot and sometimes they'll just walk into melee range instead.
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I had a really, really awesome final battle as Arkhan vs Settra.
Settra only had one town left (though I kinda left him alone up there for quite awhile while I conquered everything to the Southeast) so I waltz up there with Arkhan and his silly stack of starting units. I figure it'd be a cakewalk, since he probably has no units left. However, I end my turn out of sight of the town as I ran out of movement points.
End the turn.
Settra attacks me with two and a half stacks of units. Oh shit. Tomb Guards, warriors, Ushabti, catapult, chariots, etc. etc. You name it. I don't even know where the fuck he summoned these troops from. His last town can't possibly have all those recruitment buildings.
Nevermind. It's fine. I've fought harder battles before. Jump into the battle.
The enemy's reinforcements are coming right from my left hand side. Awesome. I can just cut them off there, rout the army, and turn to fight the main force. Easy.
The sheer enormous tide of units coming in from the left hand side completely overwhelmed all my guys, pushing straight through. I had units trapped in pockets all over the left side fighting on all sides. I think it's some kind of miracle they haven't completely crumbled. My archers are no longer archering. My poor casket of souls is now dying to Ushabti. One thing I completely forgot. Tomb Kings aren't alive. They don't rout. They don't flee in panic when losing. They fight to the death. This plan to quickly get rid of them was idiotic.
But it's okay. We're surrounded and isolated on every side, but we're somehow winning. My units have more experience and stats than theirs. I can defeat them with some rear charges by my scorpion, my chariots, Arkhan, and my Necrotect. Arkhan's chariot lets him somehow float through enemy units so it's damn good for this situation.
We kill off a huge number of skellingtons, enough to let the enemy proc their Ushabti spawn. They spawn it on some of my chariots, which is hilarious as I leave them in the middle of the desert.
Then comes Settra. At the worst possible time. He's an anti-Arkhan missile and zooms straight to my lord, who's been keeping the entire army alive thanks to the Tomb Blade AOE regeneration, and his AOE regeneration skill, and his casting spell AOE regeneration skill.
BAM!
Arkhan takes 50% of his health in damage from the one charge. It's insane. Fucking spamming Spirit Leech on Settra trying to kill him. Send the Necrotect in to help fight him off. Send the frigging scorpion in as well. Send in the RoR skelly spears with poison attacks.
The rest of Settra's army smashes in. My army is in shambles. At this point it's basically just Arkhan, the necrotect, the scorpion, the RoR skelly, RoR archers, and like... a Tomb Guard left alive. Versus a thousand-something skellingtons. The only reason these guys were alive is because they're the only guys within Arkhan's neverending regen AOE. Arkhan himself is constantly bordering on crumbling.
After like.... 8 Spirit Leeches, Settra finally collapses. A small victory, but a victory nonetheless. But the battle is not yet won. I group all my units into a tight little ball and hope for the best. Can a hundred or so bones defeat a thousand if there's enough regeneration? There's still Ushabti, probably the guys who spawned in the middle of nowhere. There's still heroes running around. I start micro-ing Arkhan like mad, using his phasing ability to constantly smash through lines, taking care not to move him too far from the circle or the regen will end.
Finally. After killing another 500 or so bones. Everything starts to crumble.
Victory.
The only things remaining are Arkhan, the Necrotect, and the scorpion.
Then the next turn I summon everything back.
¯\_(ツ)_/¯