Halo 3 - GOLD SKULL: Fog Skull
Fog Skull
Location: Floodgate
Nabbing this skull can be tricky, but messing up doesn't warrant too much backtracking as the skull can be found right at the start of the stage. As soon as you enter the town, zoom in on the top of the building to the right. Time it right, and shoot the Flood right before he jumps off the edge of the building. If you did this correctly, the skull will drop to the ground ahead of you. Watch the skull so you can locate it after it falls to the ground.