Hey, so, while we're on the subject of Pokemon using moves that they shouldn't be able to use, how does Rhyhorn use Fire Blast, Thunder, and Blizzard? Last time I checked, rhinoceroses couldn't do that!
There's a certain monster build that appears to be a Japanese trope and the Pokemon that possess this build are compatible with all kinds of elemental moves. I don't know what it's called, but it's sort of reminiscent of godzilla and includes Nidoking, Nidoqueen, Rhydon, Kangaskhan, Tyranitar, Aggron, and the like. You will notice that all those Pokemon and others like them have the same expansive movepool of energy-based attacks.