There was no MLG playlist in the original release of Halo 3, however, Bungie announced that an MLG playlist would replace Team Hardcore in matchmaking for Halo 3 on March 12, 2008. It was released online as a ranked playlist on March 31, 2008. The MLG playlist along with the other Hardcore playlists were moved to the Ranked Playlists while the Hardcore Playlist was retired as of August 4, 2009.
- MLG Amplified (Symmetrical)
- MLG Onslaught (Symmetrical)
Most games have a 15-minute time limit, however in the official MLG Pro Circuit CTF gametypes have a 30-minute time limit in case the game is tied after the 15 minute mark.
All Team Slayer games go to 50 kills.
- The Pit
MLG Team BallEdit
Team Oddball has a maximum score of 250 points.
MLG Team KingEdit
Team King has a maximum score of 250 points.
MLG Multi FlagEdit
CTF on Narrows and The Pit have a maximum score of three captures. Onslaught and Heretic go to five captures.
- The Pit
In all MLG gametypes, players will start with a Battle Rifle and two Frag Grenades. Players move at 110% speed and inflict 110% damage instead of the usual 100% for both stats. The shield recharge rate is also reduced to 90% and the motion tracker is disabled. The stat changes serve to speed up gameplay.
- Battle rifle, 10 seconds respawn.
- Frag grenades, 10 seconds respawn.
- Plasma grenades, 30 seconds respawn.
- Plasma pistol, 60 seconds respawn.
- Covenant carbine, 90 seconds respawn.
- Mauler, 150 seconds respawn.
- Sniper rifle, 150 seconds respawn.
- Rocket launcher, 180 seconds respawn. (Note: Not all MLG map variants have the Rocket launcher)
The MLG gametypes narrowed down the weaponry to a small portion to balance out the game. In the same manner, all equipment items were removed.
Power weapon respawning is different from normal in that the respawn time is exact and weapons drop from above the spawn point rather than on the spawn point. Power weapons are also only available for a limited time after respawning before disappearing.
All Powerups spawn at 120 seconds.
- Custom Powerup: There are two versions of the Custom Power-up. The Custom Power-up is only available on Construct and The Pit. Each custom power-up gives the player a 3x overshield if the player has full shield or is recharging, otherwise the power-up will be burned and no player will benefit from its effects. It takes a mere 3 seconds to gain the full 3x overshield if picked up correctly.
- For King of the Hill on Construct, the custom power-up appears for the first time after 2 minutes of play.
- For Pit CTF and TS, the custom power-up appears right at the start of the game in the passageway right underneath the sword room.
- For TS on Construct the power-up takes the form of an Active camouflage. This will last for 60 seconds after pickup. As with the Custom Overshield, the Camo will not spawn on Construct the first 2 minutes of the game.
- Active camouflage: The powerup is unchanged from the normal camo. (This Powerup only spawns on Guardian.)