I guess Frisk? I mean, it activates as soon as Banette is sent out, so I guess it would be interesting to see what item the opponent is holding (if you didn't figure it out already) before you Mega Evolve.
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Frisk would be helpful in letting you avoid wasting a turn with Knock Off if the opponent's item is something that can't be knocked off. For example, your opponent has their own mega in but it hasn't mega evolved yet for whatever reason (maybe they're trying to activate its normal form ability first). Frisk would alert you that it's holding the mega stone which would serve two purposes. You wouldn't waste a turn trying to knock off the mega stone and you would know that this is their mega so you would then be better prepared to handle it once it does mega evolve (and if it's a Charizard, you also now know which mega form you're about to face).
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I see. Frisk is definitely not as pointless as it seemed. Thought with Insomnia Banette can be a pretty fantastic counter to breloom. being immune to spore and his fighting while burning him with will o wisp. Though I guess that's a bit.. specific? Outside of breloom and mega V there aren't many sleep abusers in OU. so Frisk could be more helpful in most situations.
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