Prior to Scooby-Doo! Mystery Incorporated's "Mystery Solvers Club State Finals," many Scooby-Doo fans wanted Scooby to crossover with more clones than just Josie and the Pussycats. However, what a lot of Scooby fans don't realize is that there was a crossover with Captain Caveman in the 1970s! Despite not being advertised at all on the cover, Marvel Comics' Scooby-Doo #9 featured a crossover with Captain Caveman and the Teen Angels.
Thanks to Tom Holste for coming up with the idea for this fun fact, and providing these images!