I recently got a HA Eevee, evolved it into Sylveon, and I got Pixilate as its ability.
I then went into a Link Battle. The opponent uses Mega Charizard X, I use Sylveon. I used Hyper Beam, but it was only of normal effectiveness. Why is that?
It's because Charizard X is part fire type giving him a resistance to fairy type moves. So making a fairy type moves normal effective.