Timesplitters 

Help save mankind by traveling through time portals and retrieving time crystals that will change the course of history in Sony PlayStation 2's TimeSplitters 2. With 10 levels in single player mode, this first person shooter provides objectives for game completion as players travel through the 1920s, trek through the jungle, and blast away in future space factories. Use the challenge mode to unlock different characters, collect awards, or activate cheats that will give a player unlimited ammunition or better abilities to defeat the time hopping aliens bent on destroying humans. Play with up to four friends in arcade mode, or link up multiple systems and play with up to 15 friends. This brings on a whole new arsenal of weapons and game play in this time hopping alien inspired video game.