Find the Secret in Caustic Cesspool.

Complete all Act 2 maps on Recruit difficulty or higher

Complete all Act 2 maps on Nightmare difficulty

Land a final blow on a Boss Mutation with the LAW.

Find the secret in Plan B.

Complete The Armory

Kill a Crone with the Bow.

Find the secret in The Armory.

Complete all Act 1 maps on Recruit difficulty or higher

Complete all Act 1 maps on Nightmare difficulty

Set an enemy on fire with the Flame Thrower, while also being on fire.

Kill a Snitch without it alerting the horde.

Make a Breaker hurt itself.