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While Knock Off is more powerful in the first hit (implying they aren't using gems/berries) Crunch is only 10 less power, and has the flinch in case you somehow don't kill.
I agree that Dragon Dance is also a good stat booster, but I like Bulk Up because the only status you have to worry about...
My boy Scrafty should be pretty high up imo, the sweeper combo is too dope.
Scrafty is my favorite competitive pokemon, and he's even better in Tier Shift.
Drain Punch sweep combo isn't just the best part, you can setup so many other...