Animation number: 5250When hit by certain attacks, the character flies through the air, spinning. Mostly seen in MvC characters.
Notable examples: ??? (Jin's Saotome Cyclone does this in MvC, but I don't know any MUGEN creations that use either animation; still, if your character has sprites for it, it can't hurt to include!)
Animation number: 5251Exactly the same as 5250, but with the character's head facing down. In MvC, it uses the exact same sprites as 5250, only flipped vertically.
Notable examples: ??? (Partner tag-ins cause this in MvC, but I don't know of anything that would use it in MUGEN. But like 5250, if you have the sprites, you should put it in!)