mesh deforms fine in preview+renders, but in the GE its all funky...

i modeled and rigged a dragon, then made an animation of it flapping its wings up and rising into the air. i rendered it and its fine, and its fine when i hit ALT+A to preview the animation, but when i set up some logic bricks so when you hit spacebar the animation plays, in the GE some of the vertices are deformed or stay in place. what can i do to fix this?!

Envelopes and other “funky” functions don’t work in the game engine
So go back to the good ol’ vertex groups method
Check and recheck them