Use Thunder.
Use flying, poison or a bug type Pokemon to kill her/him.
Well i know fire works! and water might too
There are 22 flying-type Pokemon.
Flying type Pokemon are good against normal Pokemon.
Swanna is a Water and Flying type pokemon.
Crobat is a Poison and Flying type pokemon.
Find a Flying-type Pokemon and catch it. There are plenty of them in each game and many Flying-type Pokemon are common Pokemon, so you shouldn't have trouble doing so.
The weakness of flying type Pokemon is Ice, Electric and Rock.
Jumpluff is a Grass and Flying type pokemon.
The LARGEST Flying Pokemon is RAYQUAZA at 23' (7m) in length.
Fire types, flying types, and rock types are supereffective against bug types. Grass, dark, and psychic types: BEWARE OF THE BUG.
You could check Serebii.net for a list of flying Pokemon. It would be under the DPPt PokeDex.