S-Rank Pokemon are those that can function anytime, anywhere, with any support. I don't feel this is the case with MegaKen. While Blaziken is my favorite mon and its Mega forme is certainly stronger than vanilla (something I admit I didn't expect at first), but still nowhere near perfect. Giratina still is trouble, as it can easily phaze it out (although with Knock Off it can't counter it anymore), physically defensive Dialga can do the same, and any priority move still takes a huge chunk of its health. Unlike Mega Gengar, which is immune to ExtremeKiller Arceus' Extreme Speed and can wreck it with Focus Blast after hazards or LO recoil from previous attacks, MegaKen takes amazing amounts of damage from any Extreme Speed, be it from Arceus or Rayquaza. Blaziken just can't last-nearly anything it can't OHKO can OHKO it back. Speed Boost gives it the chance to be A-Rank, but it's not enough for S. Blaziken simply needs more support than an S-Rank Pokemon can afford. I already feel shaky with the inclusion of Xerneas.