Originating from a Team Fortress 2 comic, the act of aiming a lethal explosive projectile weapon such as a rocket launcher at a point-blank range in order to instantly kill both the player and a nearby enemy player in the blast radius as either a last-ditch attempt or for hilarity. This is sometimes preceded by the player who is about to fire the weapon shouting "MAGETS" over a VOIP. (Pronounced mag-its)
Guy 1: "I was out of ammo so I switched to my RPG and blew us both up."
Guy 2: "Nice mageting."
Dude 1: "MAGETS!"
Dude 2: "What?"
(Dude 1 killed Dude 2 with Rockets)
(Dude 1 killed himself with Rockets)
Dude 2: "Man, mageting ain't cool!"