>>21256748If by "everything" you mean frail-ish sweepers that are weak to Greninja's moves, sure.
Suppose you had a pokemon that actually has a bit of Special Defense?
Hell, it can't even OHKO Specially Defensive Heatran.
252 SpA Life Orb Greninja Hydro Pump vs. 4 HP / 252 SpD Eviolite Chansey: 101-121 (15.7 - 18.8%) -- possible 6HKO
252 SpA Life Orb Greninja Hydro Pump vs. 252 HP / 4 SpD Sylveon: 157-187 (39.8 - 47.4%) -- guaranteed 3HKO after Leftovers recovery
252 SpA Life Orb Greninja Hydro Pump vs. 248 HP / 252+ SpD Sylveon: 121-142 (30.7 - 36.1%) -- guaranteed 4HKO after Leftovers recovery
252 SpA Life Orb Protean Greninja Grass Knot (60 BP) vs. 16 HP / 240 SpD Assault Vest Azumarill: 135-164 (39.1 - 47.5%) -- guaranteed 3HKO
252 SpA Life Orb Protean Greninja Grass Knot (80 BP) vs. 252 HP / 252+ SpD Empoleon: 103-122 (27.6 - 32.7%) -- 75.8% chance to 4HKO after Leftovers recovery
252 SpA Life Orb Greninja Hydro Pump vs. 252 HP / 104+ SpD Mew: 164-192 (40.5 - 47.5%) -- guaranteed 3HKO after Leftovers recovery
>>21256767>top 3 fastest in OUIt's outsped by Mega-Aerodactyl, Mega-Alakazam, Mega-Manectric, Talonflame, Weavile, and most scarfers. It's fast, but it's definitely not top 3.
>perfect STAB coverageProtean doesn't actually have anything to do with coverage?
How good would Protean Caterpie's coverage be?
>97 special attack is strong now>kills damn near everythingSee above.