Ahh, yes. I remember this.
Mr. Crotch Lazers, have you ever acquired a Missingno. for yourself? I have, and it's a fun experience for a short while, until it starts messing up the graphics and overtall gameplay. There are fixes, however: Release it into the wild, or feed it a Rare Candy and it will evolve into a harmless Kangaskhan. And its attacks are as follows: Water Gun, Water Gun and Sky Attack. (Yes, I know I said "Water Gun" twice. That's because it has the attack registered in its roster twice.) I wouldn't exactly recommend you risk your old Pokemon game data nabbing one of these glitch Pokemon; I'm just sharing some firsthand experience.