they were both in a huge fire that injured them both pretty badly, Lucy lost an eye due to his father trying to keep him trapped inside the fire, but luckily kept most of both of his wings intact. Zero however was crushed under falling infrastructure and lost one of their wings. Xe also lost most vision in their eye due to glass shards being gashed across their face. both of them suffered burns to the lower parts of their bodies, but zero got the most of the damage. Lucy was however intentionally trapped by him and Zeros father, so he does have remaining scars from being dragged across his stomach.