You can play on multiplayer without xbox live but you have to go to the forge and spawn a hornet then save the map and then go to multiplayer and select that same map that you saved then play it and the hornet will be where ever you put it.
Spawning is done by pressing up on the D-pad when you are master chief in the forge and you press it again to go back to chief. When you are the oricle press X to go to a menu for the items you can spawn. Includes i think all the weapons, almost all the vehicles, teleporters, and lost of random scenery like barrels, and boxs, etc. Have fun
