I'm not sure if this counts as a Mega evolution, since GameFreak seemingly was going to go that route, but that no longer seems to be the case, as far as the games are concerned, but I'm not entirely sure about that whole situation because I really didn't play Gens 5 & 6.
Either way, let's pretend it is.
The one thing to make note of for this is that unlike the regular Greninja release, I included the metallic arm and leg guards, even though I really didn't want to. But, this is to show exactly why I don't like doing these - because the knees and elbows in KK are so fucked beyond belief that anything attached to them immediately slips through reality and appears into an entirely different location at the slightest adjustment of those nodes.
Okay, bit of an exaggeration, but you can see how annoying it is for yourself. For this release, I didn't even bother attaching them to the elbows or knees, but instead, to the upper arms and ankles, and that's the best you can get them without severe clipping.
It's so gross and I hate it and I will probably never do this again, but it's there for now. Oh, but you can turn them off with Sub accessories!
Anyways, enjoy!