Against the Utility Omastar on site, Grass Knot does 47.7% - 57%, which is a decent chance to 2HKO.
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I don't understand this.
If 57% is the maximum damage you can do, and Leftovers heals 6%, you really have like a 28% chance (i did the calcs) to 2hko? Not that admirable.
Also, I just did some calcs on Hidden Power [Grass], it seems to 2hko 100% of the time. Use it! D< (Grass Knot is 60 bp)
Edit; your set lacks psychic -______- which means qwilfish can set up.