This is mostly as a RPG zombie invasion game but in Halo style. A flood is like a zombie, but slimy and when someone is dead, small floods could eat there head and develop a new flood form.
You got 3000$ to spend on characters, weapons, allies, vehicles, equipments and Grenades.
Oh ya srry i forgot about you. Ok you see 3 giant flood forms and 1 of them is driving a small vehicles with a sort of tentacle in front of it. What you wanna do?