Board Thread:General MK Discussion/@comment-79.167.22.55-20150506185415/@comment-71.86.172.21-20150521034448

My three guesses for variations are:

Hunter - Uses ranged attacks, such as guns or other projectiles

Killer - Vicious melee fighter using claws and other melee weapons

Stalker - Utilizes stealth tactics, such as something akin to teleportation and invisibility.