The movie's scene-stealing guest star, Richard Pryor is thieving and helping the bad guys one minute, admiring and helping Superman the next. Rendered "sick" by imperfectly synthesized kryptonite, a surly, evil Superman commits mischief, vandalism, and causes an oil slick. There's a clear victory for the "good" half of his personality, though.
Strenuous fighting between super-beings, but no blood. Missiles and lighting bolts are repeatedly fired at Superman. Jimmy Olsen falls, suffers a fracture. One character is turned into a Borg-like cyborg, but reverts to normal.
A villain's girlfriend/mistress is usually in tight, revealing clothing. Superman, slightly warped by Kryptonite, spends the night with her.
A few curse words.
Tie-in to vast quantities of related merchandise. Lots of product labels appear, including Kentucky Fried Chicken. An attack on Superman literally turns into a vintage Atari video game.
Drinking, Drugs & Smoking
The 'evil' Superman gets drunk right in front of the shocked citizens of Metropolis. Another character, described as a washed-up high-school athlete, is perpetually sloshed and hostile. In both cases, these activities are disapproved of. However, Gus Gorman gets comically drunk (and tricks a guard into a drunken stupor) to gain access to a computer.