Monster Dad, monster Dad, monster Dad!

Ace is great. I'm very happy with this new reference for him, as I've struggled to show his age and body-type before -- Ace is very old, though the way that age shows appears in different ways.

The "100% monster" form is his full monster-y self, while the normal form we see here is more like a "disguised" form. See, Ace transforms on a sort of spectrum -- most of the time, he doesn't just pop between the powered down disguised form and his monster form at the drop of a hat. It's a process that can be sped up or sped down, and he can accelerate the transition on certain parts of his body (say, the wings).

The first sign that he's transitioning is his eye color -- his disguised form has blue eyes, and they become more and more green as he becomes more active. Ace is usually able to control how he looks, but if he's on edge or under stress his disguise starts to fail and he becomes visibly more monstrous. After the first Arc of TCotC, he's hardly ever at 0% energy, but he's also hardly ever at 100% energy. He's stronger and more youthful the closer he gets to his true form, while his age catches up with him faster in his mortal disguise. By the time the plot starts, his disguised form is pretty much an old man.

Ace does his best to try and keep his monster roots under wraps -- after all, the world is burning because of monsters. He wants to protect people -- and his family -- but knows that people would turn on him in an instant if they found out he was a monster.

He's trying his best to do what's right.