Kill Hermes and acquire his Boots

Rip apart 1 Olympus Sentry

Kill Hades

Discover the secret 'Hades Arm' room

Acquire the Bow of Apollo

Complete the Trainyard mission in a single player campaign.

Complete your first Hell's Gate visit.

Use the Compass.

Talk to Elika.

Win a wall mini-game in combat.

Finish story mode on Hard, without changing the difficulty setting.

Bad guys always want more power.