Weaponless Elite (Dual Wielding)
From Halopedia, the Halo wiki
The Weaponless Elite (Dual Wielding) Glitch only works on Halo 2.
To see the glitch, go on any level in Halo 2 where you have Elites as allies. All you need to do is get a Needler (this weapon works best, although you can use any weapon that has a magazine) and fire the weapon until there is no ammunition left. Then, approach one of your Elite allies. Swap your weapon with him while you are still reloading so he is in possession of it. He should drop it immediately. When he follows you, (or if you betray all of your Elite allies except him, causing him to retaliate), he will perform a humping or tea-bagging motion and just walk at a hostile. This technique can also be performed on Grunts.