Yes and yes. (Though when Ash's Pikachu infamously "aimed for the horn", it was a Rhydon, not a Nidoking. The meme still works, though.)
As for the second, Shaymin's a Legendary pokemon with two forms, Land Form (the hedgehog looking one) and Sky Form (my avatar). Shaymin transforms to Sky form when exposed to the Gracidea Flower, and reverts back at night or when frozen.