Defeat an enemy with a critical-hit headshot.

Defeat an enemy by burning them.

Complete the training facility.

Shoot down a Hunter or an Eliminator while they are jump attacking in the air.

Defeat a zombie by stomping on them.

Attack an enemy to save your partner who is grappling with that enemy.

Defeat Centurion.

Defeat an enemy with a knife.

Break free of a Cerberus while they are biting you or trying to push you down.

Complete Separate Ways on Professional mode.

Complete the main story within 8 hours.

Defeat Osmund Saddler in Separate Ways.