- Have two players sign in and proceed to the Campaign or Firefight lobby.
- While in a Campaign mission or a Firefight game, press A for the amount of players that are going to join.
- Quit the current mission/game.
- Start the game again, but this time press A for the third player a second after the final beep of the countdown. For 4 players, do the same, but press A for the fourth player a split-second after the third player presses A (just before the game says "Setting Up Game").
- In Halo 3, the game will freeze if the player comes across a Cortana HUD moment.
- In Halo: Reach, the game will lag or freeze briefly when there is a lot being rendered at once.
- This will also record your post-game reports if your profile is connected to Xbox Live.