Although its never good to be a D-lister, at least in 1991 that status alone wouldn't keep you off the screen if you were a superhero. In particular, swamp monsters were all the rage.
The animated for kids Toxic Crusaders, centered around the R-rated Toxic Avenger AKA Toxie featured hoped to cash in on the environmental movement ala Captain Planet. It earned just 13 episodes -though only 5 aired.
Around the same time as Toxic Crusaders, Swamp Thing attempted a lazy cash grab, but once again the series was short lived. And the intro theme was just brutal.
Teenage Mutant Ninja Turtles II: The Secret of the Ooze
As if audiences couldn't get enough of green mutants, the Turtle sequel arrived in the summer of '91. The first movie was a great success resulting in a rushed production for the sequel arriving just 51 weeks later.
The tone of the movie was significantly lightened and Vanilla Ice was invited to make a lengthy appearance rapping "Go Ninja, Go Ninja, Go!" The sequel was not as big a success as the original, but it still pocketed $78 million on a $25 million budget opening the floodgates for the inevitable 3quel.
The Rocketeer, on the other hand was not a success. This much underrated period film about a Nazi fighting hero was directed by Joe Johnston who would go on to direct the the 2011 live action Captain America film.
Aside from TMNT 1991's only other modest success was Disney's animated DuckTales spin-off Darkwing Duck starring Drake Mallard.
In the 90's Marvel Comics really struggled in the live action department. The slew of low budget trash (Captain America, Fantastic Four, Generation X) that got greenlit is remarkable. Even more remarkable is how the company has turned things around around. A pilot for Power Pack about a team of super powered kids did somehow manage to get made, but it was pretty iffy. Believe it or not, before Marvel Studios struck gold with Iron Man, a Power Pack live action film was one of the films named to launch the new studio. Yikes.