Hey that's ours-10GS: Beat a round of firefight only using a wraith Anti-air division-50GS: Take out a Phantom before all the units drop out.(Firefight) The next Master Chief-75GS: Beat a solo round on Firefight with all skulls on without losing a life. Don't ask for directions-20GS: Beat the game without ever using a waypoint Met the Crew- 5GS: Play as every ODST in Firefight An Ode to Froman-10GS: Beat every flashback mission in campaign using only a sniper rifle. Grenadier-30Gs:Find the first beacon with only throwing gernades.