Mortal Kombat reboot development team's design process for Fatalities, which starts with a brainstorming session. He notes on the PlayStation Blog that ideas can come from anywhere, including "gruesome murder news stories, old horror movies and actual nightmares" -- and even a 5th grader's doodles, we suppose.
Once an idea sticks, MK co-creator Ed Boon storyboards the concept, as seen above. The storyboard is then used as the basis for a motion capture session and, finally, the motion capture wire-frame data is fleshed out for use in the game by the animation and cinematics groups.
The whole process essentially boils down to good, old-fashioned spit balling. Hmmm, that actually sounds like a good Fatality for Reptile: "The Spit Ball." Pardon us while shoot an email off to Ed Boon.