Defeat The Slime Queen without taking any damage from the boss fight (you are allowed to take damage leading up to this boss fight). Barrier is ignored. If you get hit while Barrier is active, this still fails the achievement.
Defeat The Slime Queen without taking any damage from the boss fight (you are allowed to take damage leading up to this boss fight). Barrier is ignored. If you get hit while Barrier is active, this still fails the achievement.