It is quite simple, just set the deceleration on all warthogs to near 0 (not actually 0 or they won't move), then play warthog wars.
For added fun, you can set the guns to have dropped trigger lock, so once you start firing, thee turrets fire for ever!!!!
Now just make a normal game of slayer or hog wars, and laugh as people get very confused about why they keep getting run over and shot by driverless warthogs. Just act as clueless as them or pretend everything is normal, and enjoy the fun.

So far everyone online has either loved it or been VERY confused!!! LOFL