Brute Buddies
From Halopedia, the Halo wiki
The Brute Buddies glitch is an AI-related phenomenon that occurs in the Halo 2 Campaign level the Great Journey. It may be related to Halo 3's "Friendly" Brutes glitch.
Instructions
In the Great Journey, when you're escorting Sergeant Johnson's Scarab in a Banshee, fly to the ground near the Control Room and wait for another Banshee to fly down to you, hijack it. The Brute pilot will fall out and land on the ground, but he will not die.
Fly down and get close to the Brute, and he will calmly walk toward you and follow you wherever you go. Even though he is making berserker yells, he will not attack you. If you do the same with others, they, too, will follow you -- so you can have an entire pack of harmless Brutes follow you wherever you want. However, if you kill one of them, and another one sees you, he will more than likely go berserk and attack you.
Also, in the same area, when you see the overturned Wraith, get out of your Banshee. The Brute there will not attack nor have a weapon.
See Also