Alright I'll make this simple. You need pokemon that have moves that put people sleep. Moves like Grass Whistle, Hypnosis, Lovely Kiss, Relic Song, Sing, Sleep Powder, Spore or Yawn.
With those you have a good chance of knocking her out and any pokemon she has guarding her.
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With those you have a good chance of knocking her out and any pokemon she has guarding her.