Video This was not discovered by me. This is a VERY old glitch that not alot of people know. I don't even think 1 million nerds know. To do it follow these instructions: 1. Turn on 3 controllers. 2. Set your xbox to local on campaign. 3. Sign in 2 profiles and leave the other signed out. But turned on. (That's what she said?) 4. Right as you start the countdown sign in the other player, select "use temporary profile" 5. It should make sure you're sure. When the screen turns completely black, select "Yes". 6. Play
I knew about it It is an interesting glitch for sho'; a sign that Bungie originally planned to make it more than 2 player splitscreen co-op methinks. If memory serves, people said that the game totally screwed the hell up on certain missions though, so be warned! EDIT: It's the parts when Cortana flashes on the screen - it just crashes the game. Edit 2: 4 player COOP bish!
However useful this glitch may be if it crashes your xbox it means its not good for your console. It was set to 2 player splitscreen for a reason. I don't think it should be tinkered with.