Hear me out: Mega Palossand

It actually doesn't need that much explanation. Kalos (France) is a region heavily characterized by its architecture. Palossand is a sand castle, and castles are prominent in both Western history and fiction. Palossand could turn into a dungeon or gain towers or something, I don't know.

Not to mention most existing mega evolutions are bipedal humanoids, so getting a sand castle mega would be fun