|Requirements||TimeSplitters Future Perfect|
First, make sure character abilities is off. After that, go to a mapmaker map and select "Play game". Play a game with bots. Then, Go to Arcade custom and stop at the settings. Check the bot set and you will find that some of the bots have nothing in the place of their difficulty. These bots will be invincible, and can only be killed when forced into a instant-kill hazard or injected.
Another interesting note is that setting these bots on fire with a flare gun will cause them to run continously without even flinching when you shoot them with a shotgun or something similar. In this state, the bots cannot be killed, not even with an injector.