War
Its just a never ending game. Personally I love doing war with no shields. Its awesome, have B-Rifles and such on map. Its a fun game, and if you can get it popular you'll get like 40 people in one game. It gets crazy. Plus its fun to just keep playing; its a great way to get your aiming better, because its one hit kill with B-Rifle to head.
Jaws
Ok its a capture the flag game on Coag. What happens is two people are on defense and the rest are on offense. You have ghosts and Wraiths on map. The people defending can only be in the ghosts, and the people trying to get on the flag HAVE to be on the Wraith, they can't run around. (The Wraith is a boat, and Coag is all water, basically) Anyways while the Wraith tries to get to the other side of the level, the two ghosts try to splatter the people on the wraith (or knock them off and then splatter them)
The game is in three rounds; if all the people on offense die, then the round goes to the defense. If the offense captures the flag then they win the round. Also; if the driver of the wraith is the last person a live; he has to jump out of the wraith; and swim (walk) the whole way.