Underdog
Crossovers
Simon's Angels by VampBite083
An epic crossover featuring The Powerpuff Girls and Underdog. After their latest defeats to The Powerpuff Girls and Underdog, Mojo Jojo and Simon Bar Sinister, respectively, find a legendary treasure that they hope will be the answer to their problems. Action, adventure, epic fights, cameos, a slice of humor, many different references, and an excellent soundtrack are all included!
Crossover - Powerpuff Girls & Underdog - Rated: M - English - Adventure - Chapters: 2 - Words: 8,834 - Updated: 2/15 - Published: 2/13 - Blossom, Bubbles, Buttercup, Mojo Jojo
Rocky and Bullwinkle in: “Underdog Returns” or “Literal Atomic Dog” by Ek01
In this crossover with Underdog, Rocky and Bullwinkle team up with said superhero to take down the grandchild of one of his old villains, who in turn teamed up with Boris and Natasha.
Crossover - Rocky and Bullwinkle & Underdog - Rated: K+ - English - Sci-Fi/Parody - Chapters: 7 - Words: 2,937 - Favs: 1 - Updated: 2/18/2022 - Published: 2/10/2022 - Complete
It's a Dog's Life by Evil Little Dog reviews
Talking dogs should probably be the least of their worries, but, there you go.
Crossover - Underdog & Avengers - Rated: K+ - English - Humor - Chapters: 1 - Words: 502 - Reviews: 7 - Favs: 12 - Follows: 5 - Published: 7/31/2013 - Iron Man/Tony S., Hulk/Bruce B., Nick F. - Complete