ME3: Explore a lost city.

ME3: Dispatch 10 probes to retrieve people or resources in Reaper territory.

ME3: Defeat a harvester.

ME3: Destroy an Atlas dropped from orbit.

ME3: Stop a Cerberus kidnapping.

ME3: Bring a veteran officer aboard.

ME3: Visit a store on the Citadel.

ME3: Perform any combination of 50 biotic combos or tech bursts.

ME3: Return to active duty.

ME2: Keep your team alive through the suicide mission

ME2: Save humanity throughout the galaxy from certain annihilation

ME2: Use the Omega 4 Relay

ME2: Hack a geth collective