Mikey, Robo Donnie and others in “Unfinished Business”

Leo! You're back, Bro.

We looked everywhere for you. We thought we lost you forever.

What happened to you? Last time we saw you that Mutagen Bomb went off.

It's all starting to come back to me; piece by piece. I remember. I... was there. I remember pushing you all to safety but I was caught in the middle of the blast. It mutated me into this horrible thing. But now, somehow, I'm back. Thanks to all of you.