Complete the story's opening sequence in any mode.
Get a letter grade in all eight finales in any mode.
Be on the winning team in 100 arena matches.
Be on the winning team in one arena match of every mode.
Find a secret level.
Free a fellow prisoner.
Get yourself a cool new weapon.
Free 50 prisoners in the Gift Shop.
Collect all the prisoners of one head shape.
Free all the prisoners in the Gift Shop by unlocking or trading.
Collect all the weapons in the Gift Shop by unlocking or trading.
Complete the first four finales in any mode.
Make a trade with someone.
Trade online with ten different players.
Kill your teammate 50 times.
Get 100 kills.
Play with the Behemoth or someone with this achievement in an online game.
Successfully use every melee attack move.
Use each weapon successfully.
Die enough times and we give you a prize.
Get eaten alive.
Play and rate 10 user-created levels.
Get an A++ in 10 levels.
Download and host a game of user-created levels.
Get a letter grade in every level (except Encores) in Normal Solo Story Mode.
Get a letter grade in every level (except Encores) in Normal Co-op Story Mode.
Get a letter grade in every level (except Encores) in insane solo story mode.
Get a letter grade in every level (except Encores) in insane co-op story mode.
Complete all the Encores in any mode.
Collect 10 Golden Hats.
