Some TMNT stuff really isn't for little kids.
In issue 14, Lurch bound itself with Donatello's cyborg symbiote armor, telling the Turtles that Don was not dead, as had been claimed, but that his spirit was "elsewhere" (the Astral Plane), before flying away.
In TMNT Urban Legends #24, the armor resurfaced as Lady Shredder, taking over Karai's daughter, who was left in a vegetative state due to the events of City at War. Lurch (Who has developed an immunity to the nanites) was drugged up and left morphed into Amai, giving the other characters reason to doubt that Lady Shredder was indeed using Amai's body.
In TMNT Urban Legends #25, he escaped with the turtles and Pimiko.
- Lurch's transformation into the female Turtle was a deliberate finger in the eye to Venus de Milo and her fanbase.