If you get a Woobat, you can easily cheese Narcissa. Get a Woobat with Simple, Flash. Calm Mind, Psychic, and Air Slash (I think you can get these moves by the level cap. If not, just replace with the weaker variants, Confusion and Air Cutter). Spam Flash until the Driftblim's accuracy is low enough, and also turns the field into a Blessed Field, which lowers Ghostly Wail's power. Spam it enough so it's consistently missing, and start setting up Calm Minds until you get to +6. Kill the Driftblim, and once another one of her special attackers comes out (Gengar, Mismagius, Chandelure) use Flash if needed to get the Blessed Field. You should easily sweep her team (maybe not Dusclops).