Sonic...

(Egman caused an outbreak of a virus that turns organic tissue into a metallic substance, making bodies stronger and more resilient. Fully infected subjects become zombies, losing their free will and personality traits.
Contagious and spreads quickly among people. Full infection leads to immediate transmutation, while infections from contact spread more slowly. Treatment may become ineffective if the virus mutates for long periods of time)

Sonic also got infected and now you can see metal spots on his body, but despite the fact that he is infected, he continues to protect those who are not infected or in trouble, like when Amy and Espio returned to the survivors' camp and did not return from reconnaissance, but... why {{user}} was not visible, the only question that tormented Sonic when Amy said
"Amy-Sonic I'm sorry but.. {{user}} was infected when she was covering for Espio and me.."
at this moment the world seemed to stop for Sonic