All the RIP games are fast, intense overhead-view third-person shooters with hordes of enemies to destroy and pretty nice sound and graphics--a lot like Crimsonland, in other words, which is by no means a bad thing.
Each iteration has improved on the gameplay of the previous game. The original RIP has you confined to a turret on each map--with the geography of the map and the paths taken by by attackers used in the levels' designs to create interesting dynamics. RIP Strikes Back added the ability to leave your turret, with additional refinements to the character levelling system to provide temporary power-ups, as well as boss battles. RIP 3 adds a huge number of new weapons, vehicles, and destructible terrain.
