>>57996958
>Why not just change their color scheme?
They've been wanting to do the type change gimmick as far back as gen 3, as seen with the Delta Species cards. They most definitely felt like a recolor or colored aura wasn't obvious enough for people to be able to tell right away what type they've switched to. It only worked on cards because they could change the whole card color to the new type, not having to worry about the art as much. So this is why Tera ended up so big, flashy, and obvious.