Under the mask - I part

The continuation of the Fast Forward: Darrius Dan (I do not know about the name) found the way to destroy turtles, by using Dark Don as a replacement for true Donny thanks to the special tecknology that enables transfer the mind of the clone to the ninja turtle's body. Now Dark Don has to find out about the Time Travel Window and also get rid of the rest of the turtles by replacing them with clones. Who will be next?