All There in the Manual: After a fashion. By default, your only hint of a storyline is the single intro screen you see when you start up the game. However, there's a menu option in the pause screen that gives you an extra paragraph of text, and the game came bundled with a comic book that explained the game's backstory in much more detail.
Anti-Frustration Features: The ring levels allow you to miss a few of the rings (equal to the number of rings that are gold). Also, if you fail a challenge after a ring level, you normally have to play the ring level again, but if you've already cleared the ring level 3 times, you can keep retrying the challenge indefinitely.
Superman villains Jax-Ur and Bizarro appear in the game's tie-in comic and are implied to be involved in Lex Luthor's plan. Neither villain appears in the actual game, though a photo has surfaced of Bizarro in level 8, presumably originating from the game's development.
Easy-Mode Mockery: The best ending is only available if you complete the game on the hardest difficulty.
Fake Difficulty: In level 6 you must escort Lois from the end of the stage to the start. If you get too far away from Lois (i.e., she exits the game's hideously short draw distance) a new enemy spawns next to her and you have 15 seconds to go back to her.
Fission Mailed: It's possible to make it so that Lex Wins, and then proceed into the next part of the stage. One example shown here has Superman intentionally fail by hitting a woman with a box, but she still walks to the finish if you wait a few minutes.
Floorboard Failure: Happens unintentionally sometimes, when Superman suddenly drops through the floor onto the base of the level. And when it does, you have to start the level over, since there's no way to get back up to the "floor"
The game is notorious for its unbelievable abuse of Pass Through the Rings, but that only covers the odd number levels, or "Ride Stages." What follows afterwards is a set of ridiculously cramped buildings with simply painful fighting mechanics.
Think the ring stages are bad now? Wait until you get to the ten minute long one. The most of the ten minutes are necessary long one.
Then there are ring stages where you fly around and literally loop back to where you started from. No, you can't just fly into the last ring either, you have to do it the old fashioned way.
Starting in the second ride stage, the rings actually start moving. And they eventually move in rapid but small circles, making it even harder to fly through them.
In level 6 you must escort Lois to the start of the stage, where she will be ambushed by Metallo. Leave Lois to fight Metallo and—as usual—a Dark Shadow will spawn next to Lois. Normally the level ends when you kill Metallo. If you kill Metallo and a Dark Shadow is still around, the game glitches and the level doesn't end, forcing the player to restart.
The final level has a time-machine puzzle where Superman must travel through portals to adjust a number to the value 2000. This puzzle is heavily glitched and the player will drop dead at complete random. This glitch does not render completion impossible, but it does severely complicate completing the level.
Under certain circumstances, you can still be killed in the "Superman Wins" end-of-level screen.
You can also die in the cutscenes. If you're in a room with Kryptonite, your health will keep draining. And draining. Until Lex wins.
Kryptonite Is Everywhere: The game has "Kryptonite fog" in every level, diminishing Superman's powers. Of course, it's just an in-game explanation for the severe distance fog that was supposed to mask the Nintendo 64's poor draw distance.
There are so many glitches in this game that, despite its notoriety, no comprehensive list of them even exists.
Sadly, there's footage on YouTube of an actual beta of the game. And it's arguably better than the release product. The producer of Superman 64 primarily blamed it on the licensers digging their hands messily in the development of the game, and that apparently a massive amount of the code and assets had to be redone mere months, if not weeks, before release. With the ROM of the beta now available, the general consensus is that while the controls are only slightly better, the lack of rings and reduced occurrence of flight stopping glitches make the beta far more playable than the final product.
Pass Through the Rings: The "Ride Stage" odd number levels of the game. Believe it or not, these are the tolerable parts of the game.
Sequence Breaking: Thanks to the glitches in the game, some stages are possible to beat very quickly by skipping most of the levels.
Shaggy Dog Story: You defeated Lex in the virtual world... but the real Lex is still out there.
Skippable Boss: It is possible to clear the LexCorp stage by ignoring Brainiac and going straight to reading all the notes on Luthor's desk.
Despite the game being simply called Superman (or The New Superman Adventures Aventures [sic]), it quickly became known as Superman 64 to distinguish it from other Superman games.
The Angry Video Game Nerd made a joke about this in his review of the game. Everyone expected him to do this game, but he started the video saying: "Superman...on Commodore 64. Yeah, that's what you mean, right? The Commodore 64? [...] The game came on floppy disks. Remember those: the ones that actually are floppy?"
The ride stages are notorious, as are the mini-games between ring tunnels. The first mini-mission has a tight timelimit, which is barely enough time to react. There is also a timed mission where no timer is displayed, where you have to use super breath on three tornadoes.
Every single Maze level has a timed section as well; usually a timed puzzle on top of that.
Useless Item: In stage 6 it is possible to find an X-Ray vision power-up (the game only allows you to use Superman's powers after finding power-ups); as far as players can tell, using X-Ray vision does absolutely nothing.
There's a level where you have to protect Lois from enemies as she marches out of the building. What you're supposed to do is freeze her with your super breath and encase her in ice that's a foot thick so the enemies shooting her don't hurt her. Scouting ahead and killing the enemies before she gets to them? No; the game screws you if you do that!