In "Which Came First?", when a field trip across the desert is ruined by the school bus' flat tire, Billy, Mandy and Grim go into a cave infested by giant mutant chickens. In "Substitute Teacher", Nergal Junior's first day at his cousin Billy's school results in him being bullied by Sperg, so he transforms into Ms. Butterbean, the school teacher, to exact revenge.
Did You Know?
At the end of "Which Came First" after the mutant chickens have been killed, Irwin is seen eating one of the chickens, then another Irwin can be seen walking past with a chicken on his head in the same shot. See more
[Sperg throws an eraser at Nergal, Jr., hitting him in the head
Can he do that, Ms. Butterbean?
[Sperg tosses an apple at Ms. Butterbean, who puts it in a drawer full of apples
Why... yes, yes, he can. He's bigger than you.