Not as much gaga as a bed of nails and someone returning from Mount Coronet, but it works.
The next Mega Evolution for Pokemon Legends: Z-A is a candidate for the Rey de Voladores title.
A video was posted today confirming Mega Hawlucha would be available in Z-A. The luchador-inspired Fighting / Flying type sports a more ornate mask with gold trim, as well as larger wings.
Although Hawlucha and Mega Evolution were both introduced in Pokemon X and Y (2013), Hawlucha is only the second Pokemon of that generation to have a Mega Evolution, and the first that can be reasonably encountered in a playthrough since the only other one is the Mythical Pokemon Diancie.
