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Im the TuxedoSpheal, and i think that greninja should be ban because the coverage he has, and his ninckname, "no switch in" really speaks for it self. Not too many pokemon wall greninja, or even check him, and you never know if your opponent has the upper hand on you if he has a specific move or not.
Ladder is definitely more forgiving without Greninja I mean my crappy test team even made reqs, and that would have died in a heart beat against standard Greninja.
On that note I am sad that I didn't see much Mega Diancie's on the ladder :( She's a lot more usable now without Greninja on the wings to revenge her.