[i]SPOINK bounces around on its tail. The shock of its bouncing makes its heart pump. As a result, this POKéMON cannot afford to stop bouncing - if it stops, its heart will stop.[/i] -Ruby Pokedex Entry

I didn't just want to do a bunch of Ghost pokemon right off the bat (cause most of the terrifying ones are, of course, ghosts), so I decided to do this rather unsettling one with Spoink basically having to eternally bounce or his heart stops and he dies. I don't think it came across well in the drawing, but still.