Complete the indicated task to unlock the achievement.

Achievement	How to unlock
Brute Force	Beat the brute.
Daybreak	Unknown.
Firefighter	Beat the demon.
Mathematician	Beat the calculator.
Nightfall	Unknown.
Ninjutsu	Beat the ninja.
Rocky	Beat the game with Quake.
Self Reflection	Beat the aliens.
Shattered Crown	Beat the dark king.
Sword Bros	Beat the samurai bros.
Teardrops	Beat the game with Shiver.
Toasty	Beat the game with Torch.
Tough Cerebellum	Beat the zombie queen.
Wheel... Of... Pain!	Beat the robot.
Wispy	Beat the game with Gale.