I have a Scizor in Pokémon Y. It's supposed to learn Iron Head at level 53........but it didn't. Is it some sort of glitch? Is it not supposed to learn it? Someone help!!
Scizor learns Iron Head at level 53 in Gen V.
In Gen VI, it learns Iron Head at level 50. If you want it to know Iron Head, use a Heart Scale to reteach it.
Bulbapedia - Scizor