Frankenstein Jr. destroys the Junkzilla robot's left arm, but in the next scene the arm is like nothing ever happened to it.
Buzz: You've had it, Junkman.
Junkman: That's what you think! (pulls lever revealing a cannon in his robot's left arm) I'm not through by a long shot.
Buzz: Shatterin' shrapnel! Hand grenades!
The Junkman: Wrong, boy scientist, Finger grenades.
Buzz: Flying ferris wheels!
Buzz: Well, it's like that old saying, one bad turn deserves another.
Buzz: Sufferin' scavengers! There's that malicious mastermind now!
Frankenstein Jr.: What's wrong, Buzz?
Buzz: Plenty! The Junkman is back in the villain business again and we've got to stop him.
Frankenstein Jr.: Then we'd better strike while the iron's hot.
Buzz: Jumpin' junkyards! The Junkman has built another cast iron contraption to use in his one man crime wave.