BlitzGirl41
Well-Known Member
The trailer explicitly says it is a wild Kangaskhan (やせいのガルーラ): https://www.youtube.com/watch?v=NTt65qAkR84
On the other hand, there were trailers with wild Politoed, Garchomp, Magnezone and Sylveon, so maybe it's not THAT reliable.
Also, wild Pokemon cannot spontaneously Mega Evolve, tying back to the original discussion at hand. Though it doesn't disprove that Mega Evolution does not exist, there's just no way we'd see a wild Pokemon or a standard Trainer using that mechanic (at least, purely based on previous games. Only the Elite Four used Mega Evolution).