WOW i thought there was no cheats for this game! The playable races are: Flood and robots. i havnt figured out the covenent yet.. to unlock Flood, in level 1 , kill every marine you see. Then let a grunt kill you.NOT AN ELITE!Next get to the last level.press Y to change to second weapon, then press,R,R,R,L,L,L,UP,UP,UP.LEFT,UP,DOWN. If you did this corectly you should here a grunt scream and curse.look in multiplayer and you will have most flood members to play as.(note:cannot play that dude that spawns little floods)For the robots, find a robot and let it kill you.(robots arnt until a fair bit in the game).Come back and throw a plasma g\ranade at it and make it stick.Now walk up to the robot and let the explosion kill you.Now you have done that,go to multiplayer and pick any type of game with a banshee in it.Now fly the banshee upwards until it stops then press X,Y,A,A,A,X,R,R,R,L,L. if done right, u will hear and see the banshee blow up excatly 6 times(does anyone know why?) i hope this is helpfull to you.If anyone knows how to get covenent pls tell me
after you are killed by the grunt, do you have to beat all the levels until you get to the last level, or can you save and quit then go to the last level. That's what i did and it didn't work.