This led to his dealings with the Kraang and ultimately placing his want to kill Splinter over his own survival, resulting in being mortally wounded and subjecting himself to a refined mutagen to heal his wounds while gaining new power.
This led to his dealings with the Kraang and ultimately placing his want to kill Splinter over his own survival. His fight with Splinter during the Triceraton Invasion resulting in being mortally wounded and subjecting himself to a refined mutagen to heal his wounds while gaining new power.