>>35631430It was okayed because they picked it up where the original tank-dragon idea left off, and just turned it into a hydra(or Pokemon-ified Yamata no Orochi based on the interviews). The wings are the way they are because the designers didn't want to clutter the design with the other 5 heads(Orochi has 8) so they made it so if you look at Hydreigon's shadow, it looks like it has extra heads. That's the official explanation.
What design aspect I <i>can</i> defend about Hydreigon though, is the legs. I honestly have no idea why so many have a problem with the legs, because there's an actual real, biological reason for that, and its called Vestigial limbs. Sometimes, evolution doesn't completely get rid of the appendages an animal's ancestor used to have. In some species of whale and snake, you could actually see small stumps where what might have been back limbs used to be. In Hydreigon's case, when it evolved and gained not two, but SIX wings, its legs must have atrophied because there was, biologically, no longer a use for them. It makes sense and again, I'm surprised so many take issue with it.