Ok, so: Dragons have tough scales that are hard to penetrate. Aden won't end up looking like a freakish lizard man, though. His skin will still resemble a human's but will be really tough, thus giving him better defences.
He's also be able to fly when on a normal planet, something that apart form Anya (who is flying type) nobody else will be able to do. If they're in Space, they all float around. Aden and Anya will be faster in this environment.
Aden will also, to an extent, be able to summon meteors (like Draco meteor) but when in physical contact will get into a rage that will be difficult to stop (Outrage).