Rendez-vous in Fort Santa Monica. (Complete "Brave New World" on any difficulty.)

Kill your first enemy in the Call of Duty® Ghosts campaign.

Open the door to the Temple of Euryale

Topple the Temple in the Bog of the Forgotten

Acquire Cronos' Rage

Acquire Rage of the Titans

Power up any item

Climb from the pit of Hades

Collect all of the Muse Keys

Win the first Cerberus fight

Earn a trophy in Seasons

Complete the Challenge of Atlas