I cannot explain greatly, but you need to keep a combo bonus to keep the game going. It's great with 2 players, not so much with 1 player. You get specialist bonus pretty much, and some new perks that regen health quicker and such. You pick up weapons like old school mode in COD 4, and can pick up off the ground flashbangs and C4 and such. Care packages come in on random parts of the map, it is imperative to pick those up! Combo freeze is the best thing to get! If you get it, save it for when you are in a sticky situation. This game mode is so fast and exciting that my heart is still racing... LOL! Hard to explain, but I tell you it is great.