The entire set of Chaos Heroes in Dawn of War II: Retribution (along with several others, but none nearly as bad as these guys), as with the correct skill allocation:
- Eliphas becomes ludicrously tough, gets an Aura that drains the life of nearby enemies and gives said life to him, has a chance of summoning a demon whenever he kills an opponent and has an AoE ability that does massive amounts of damage (which basically refills all his health to full as well.)
- Neroth can render any enemy completely unable to act for as a near-indefinite amount of time (any damage he takes while doing so goes to whoever he's holding, naturally) and can get an item that makes his powerful "Doombolt Volley" spell his default attack (which stacks with his "Doombolt Volley launches twice as many bolts" skill.) He can also create copies of enemy units.
- Varius gets a similar Aura to Eliphas's one, with the bonuses of healing nearby allies and having both allies and enemies who die whilst inside it (or enemies killed by him) resurrect as zombies.
- Kain can do massive amounts of damage from afar with Heavy Weapons and can, if equipped with a Lascannon, fire a MASSIVE beam of energy that near insta-kills any enemies caught in it. He can also replicate Varius's Aura for a short period of time.
The ACTUAL ARMY they have with them is just icing on the cake.