Season 4, Episode 16 - "Bebop and Rocksteady Conquer the Universe"
22 September, 1990
Zach sees Rocksteady and Bebop arrive through a portal, but because of a Turtle Com malfunction, he cannot notify the Turtles. He follows the two mutants, who steal an Anxietron Ray for Krang and Shredder. It has the power to make people frightened of anything. While testing out the ray, Bebop and Rocksteady start thinking that they could rule the world with this ray gun. They zap Krang and Shredder with the ray, turning them into cowering fools.

