So, Was messing around on my friends Halo 3, Specifically forge, and Using the Instant respawn for items trick, I created something I find rather funny.
1) place respawn point, I find high ground works best
2) put a Huge stack of propane tanks around it
3) Make sure they instanly respawn whenever any tank is destroyed
4) add grav hammer next to respawn point
5) make the rest of the map normally
6) Get someone in their and swing the hammer
7)??????
8) Enjoy being spawn killed by the Comp.