It looks like you're new here. If you want to get involved, click one of these buttons!
I rewatched The Fifth Element recently (didn't like it as a kid, gave it another shot after reading The Incal and thought it was delightful; the cut from Oldman realizing he got an empty case to Jovovitch cackling had me laughing my ass off), and that's in a similar vein: it's a comic book movie without being sourced by an actual comic book. Moebius comics instead of superhero comics, but still.
And it's stretching the definition, but I feel like Support Your Local Gunfighter is essentially Bat Lash with the serial numbers filed off. Then again, both it and Bat Lash are just Maverick minus the family element, so I dunno.
Oh! Mister Freedom. Mister Freedom is another example of a comic book movie sans actual comic.