Complete the sixth mission of the U.S.S. campaign.

Complete the fifth mission of the U.S.S. campaign.

Achieve a 5 kill streak in a Versus match.

Fully upgrade an ability.

Heal with 101 Green Herbs (lifetime)

Revive 31 teammates (lifetime)

Kill an infected teammate with a headshot before they become a zombie in any mode.

Purchase all abilities for one character class.

Infected 13 times (lifetime)

Kill 5 enemies with Blood Frenzy in a single campaign game or multiplayer match.

Witness the beginning of the Raccoon City outbreak.

Clear the giant slide.

Upgrade a weapon.