Halo CE

Vehicles. Get in a ghost and run people over. Use cannons to freeze them in place and drive over them. when driving a warthog, help out your gunner by running enemy's over. It even works in a banshee, just fly down and splat. Watch out from sticky plasma grenades though. Also, the guns on vehicles all have unllimited ammo and renger from powerful rapidfire AR (warthog) to plasma cannons (ghost/banshee) heavy guns (rocket hog/banshee cannon) and tank turrets (tank). Have fun...