In Mortal Kombat 9 (2011 version) for the PS3 and Xbox 360, each character has multiple fatalities that they can perform at the end of the match.
This is the list of all finishers (two fatalities, one babality, and one stage fatality) for Raiden.
All of these moves can be unlocked and added to your moves list by performing them in either Arcade Mode or Versus Mode.
Looking for more finishing moves? Check out my complete fatality guides:
Fatalities and babalities for Mortal Kombat on Xbox 360
Fatalities and babalities for Mortal Kombat on PS3
Raiden’s Fatalities & Finishing Moves
Xbox 360
Just A Scratch — Down, Forward, Down, Forward, X within sweeping distance
Transplant — Back, Forward, Forward, Down, B within sweeping distance
Babality — Down, Back, Down, B in jumping distance
Stage Fatality — Down, Down, Down, Y at close range
PS3
Just A Scratch — Down, Forward, Down, Forward, Square within sweeping distance
Transplant — Back, Forward, Forward, Down, Circle within sweeping distance
Babality — Down, Back, Down, Circle in jumping distance
Stage Fatality — Down, Down, Down, Triangle at close range