Have Savage Dragon and Superman met up in the real world comics? I have a feeling Dragon would be able to give Supes a run for his money.
Against the whole Justice League, though . . . maybe not.
It’s back to the 60s for the JLA as they go up against one of their mightiest foes . . . er . . . some kid who got powers.
Sinistro, Boy Fiend, was a short lived character from Charlton comics whose secret identity was the wonderfully named Jack Biceps. He also, judging by the posture on the cover above, had a really bad back problem.