Gotham City Impostors
Gotham City Impostors is a multiplayer fps that pits Batman impostors vs Joker impostors in Gotham City while Batman is away.
Steam Causing Slowdown
If you've purchased the game on Steam, don't run it from steam. Go to C:/Program Files/Steam/steamapps/common/gotham city impostors/Impostors.exe Run the game from Impostors.exe instead of Steam. The game runs significantly better without the Steam overlay.