Unlockable Raid Mode Difficulties:
Unlock the following difficulties by performing the corresponding tasks in Raid Mode:

DIFFICULTY – HOW TO UNLOCK
Trench Difficulty – Complete all Raid Mode stages on Chasm Difficulty
Abyss Difficulty Contributed – Complete all Raid Mode stages on Trench Difficulty

Unlockable Raid Mode Stages:
Unlock the following stages for Raid Mode by performing the corresponding tasks:

STAGE – HOW TO UNLOCK
Raid Mode Bonus Stage 21 – Clear the game
Raid Mode Stages 1-7 – Clear Episodes 1-3
Raid Mode Stages 13-17 – Clear Episodes 7-9
Raid Mode Stages 18-20 – Clear episodes 10-12
Raid Mode Stages 8-12 – Clear Episodes 4-6

Unlockables:
Unlock the following bonuses by performing the corresponding tasks:

BONUS – HOW TO UNLOCK
Hell Difficulty – Complete the game once on normal
Hydra Shotgun – Complete the game on Normal difficulty or higher
Infinite Rocket Launcher – Complete the Game on Hell difficulty
New Game – Complete the game once on any difficulty.