Based on Attack of the Mutant, book #25 of the original Goosebumps series.
Skipper Matthews loves superhero comics, but things go strange when he ends up in an adventure involving one of his favorite supervillains.
The episode provides examples of:
- Adam Westing: The Trope Namer himself as the Galloping Gazelle in the TV episode and video game. It seems fitting that the Galloping Gazelle is a Large Ham and a Dirty Coward.
- Adapted Out: Skipper's sister Mitzi is not featured.
- Chewing the Scenery: The Masked Mutant absolutely devours every scene he's in.
- Evil Laugh: The Masked Mutant has a very distinctive one. After Skipper defeats him, he lets out one of his own as an Ironic Echo.
- Foreshadowing: When Libby is walking away and Skipper turns away for a moment, she vanishes. After The Reveal, we see that the Masked Mutant's powers apparently include teleportation too.
- Objectshifting: As with the original book, the Masked Mutant can transform into any animal or object; however, instead of being disguised as a desk when Skipper and the Galloping Gazelle infiltrate his office, he takes the form of a chair and waits until the Gazelle makes the mistake of sitting on him. Cue immediate constricting attack.
- Recursive Canon: An advertisement for the Goosebumps TV show appears on the side of the bus Skipper rides in.
- Surprisingly Happy Ending: Skipper finds out he has become Elastic Boy for real, superpowers and all. He gives an excited laugh about it.
