Complete mission 1: "Homecoming"

Follow orders and defeat all liabilities.

Purchase 5 weapons.

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

Kill 5 enemies while using a zombie as a shield.

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

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

Revive 31 teammates (lifetime)

13 Parasite Zombies killed (lifetime)

Purchase an ability.

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

Reach "The Dark Lord" ending.