As of 22 November 2014, here's a list of bosses that can appear in normal boss battles:

Special bosses

These types of bosses are generated on-the-fly. They can be disabled in system.dat, but if not, there's a chance that a special boss will appear instead of normal bosses.

Monster Warmachine (level 10-250)

The monsters build a large tank-like warmachine to fight the Allied Forces. There are three warmachines. One is selected depending on the level.

Crystal Shadow Warrior (level 16+)

Conventional tactics will not work against the Crystal Shadow Warrior. This battle will require thinking outside the box to win.

Doppelgangers (level 50-100)

Evil doppelgangers of the players in the battle will appear to fight them. Use your knowledge of yourself and each other to win.

Bandits (level 50-200)

A bandit leader and a number of minions will fight the heroes.

Gremlins (level 50-200)

The tricly gremlins from the movie Gremlins have taken over a nearby school. Remember: don't feed the gremlins after midnight, don't get the gremlins wet, and sunlight will kill them.

Dinosaur (level 50-500)

The players must defeat a powerful dinosaur that escaped from Jurassic Park.

Pirate Ship (level 75+)

Similar to the bandit gang, a pirate leader and minions will attack, but one of two special bosses will appear when the leader is defeated.

Demon Wall (level 100-299) / Wall of Flesh (level 300+)

The heroes will be brought to a special hall battlefield and forced to battle the demon wall. They will only have 15 turns to defeat the Wall, before it crushes them at the end of the hall, though Holy Aura can still hold the Wall back.

Predator (level 200-5000)


Dragon hunt (level 500+)

The dragons hide in their lairs to prepare to attack the Allied Forces HQ. As such, they don't appear in place of normal boss battles. Players must seek them out using !dragon hunt outside of battle.