During the PAX Prime 2012 panel hosted by 343 Industries, it was announced that the popular multiplayer mode Grifball will be an official multiplayer mode for Halo 4.
Grifball was invented by Burnie Burns of Red vs. Blue creator Rooster Teeth using the Forge engine in Halo 3, which was basically the Oddball multiplayer mode, but with all players only owning energy swords or gravity hammers. The multiplayer mode was eventually folded into Halo: Reach for special weekends.
Halo 4 is due to be released on the 6th November 2012 for the Xbox 360.