From Halopedia, the Halo wiki
- Start the level Oracle on any difficulty.
- Make sure you have an Energy Sword.
- Play through until the part where the Commander Sesa 'Refumee protects himself using a type of Force Field.
- Wait until Rtas 'Vadumee says I'll follow when our reinforcements arrive.
- Switch to your Energy Sword and melee 'Vadumee through the door and onto the elevator.
- Fight off any Flood Combat Forms, Infection Forms and Sentinels while keeping Half-Jaw on the elevator. Alternatively, you can just start the elevator, while your enemies attack you.
- Start the elevator.
- As soon as the elevator starts up, Commander 'Vadumee will disappear using the same animation seen when the Gravemind teleported the Arbiter and Master Chief.