Donatello began the Image Comics series by being shot by cyborgs. He survived this though, as he became a cyborg, himself, after his body was partially destroyed from being shot and dropped out of a helicopter, with one of the cyborgs which he merged with. He maintained a positive attitude nonetheless, although he was constantly at risk of losing his mind to the cyborg half). The merger was permanent, so Donatello never returned back to his old self in the Image Comics.
This stark change meant that the CPU of the cyborg and Donatello often fought for dominance of the body. Donatello also seemed to have become a lot more aggressive, as he shot some Kunoichi without batting an eyelid.