1: Slayer- Regular death-match
2: Biggest Army- Whoever has the biggest army at the end of the time limit wins! (can attack a base and kill their units to slow them down)
3: Terrotories- Capture terratories! at a clash with 2 or more teams attacking one another, the team their first still has it until some other team can take over it!
4: Defend the Control Room- defend the buillding that is assigned to defend! if destroyed, the team looses!
5: Capture the Forunners- as said by mcz, capture the forunner's holy objects!
6: Survival- as suggested by many, defend your milita from the infected beings