Why is there a spiky- eared pichu? Can you get it in x and y?
The "Spiky Eared Pichu' was a special event in Heart Gold and Soul Silver Versions. They are no longer available without PokEdit or such places, so no, it's not available in X&Y
It exists because it was in the movie Arceus and the Jewel of Life as Damos's friend.
You can't get it in X and Y unless you trade it from Heart Gold and Soul Silver, since it was an event Pokemon in those games.