Just about everything we can learn today about video games is fact-checked or verified to some degree. But there was a time when the weirdest rumors and strangest stories were passed around the playground and cafeteria, growing from fodder for the imagination to accepted truth. The result is a layer of mystique that gets added to some of our favorite video games.

That’s right, we’re talking about video game urban legends. While most such urban legends turned out to be elaborate hoax or misunderstanding, their impact on the culture remains. Here are eight of the most memorable urban legends in gaming.

8. The Secret Cow Level of Diablo

The original Diablo featured a mere sixteen levels of monsters underneath a small town with lots of cows wandering around. When the players clicked on them they would moo, and as they kept clicking, the moos became more and more agitated. Somehow, the rumor went that if you clicked the right way, you would be transported to a secret level featuring evil axe-wielding cows. It was bull, of course.

The legend became so big that developer Blizzard Entertainment began referencing it in other games: “There is no cow level” was a cheat code in Starcraft and a loading screen tip in World of Warcraft mentions the cow level. Eventually, Blizzard gave in and included secret cow levels for laughs in Diablo II and Diablo III.

7. Confronting Sheng Long in Street Fighter II

In one of Ryu’s early victory quotes, he alludes to a mythical figure known as “Sheng Long.” At least that’s how the legend goes. But the reality is that “Sheng Long” is actually a mistranslation of Ryu’s “Shoryuken.” What was originally meant to be a boast about his Dragon Punch became rumor of a secret character to defeat.

Of course, the rumor would be a lot more innocent had a famous video gaming magazine not gotten involved. Electronic Gaming Monthly promoted the rumor as part of an April Fool’s Day prank in which they explained how to unlock Sheng Long. Most other magazines took EGM’s instructions as fact and up to now, people still believe in the legend of Sheng Long.

6. Killswitch, The Game That Deletes Itself

One of the most infamous video game urban legends is like a really great creepypasta. “Killswitch” was supposedly published in 1989 and lets you play as either a girl named Porto or an invisible demon named Ghast. Only 5,000 copies of the game were produced by the “Karvina Corporation,” and the legend goes that “Killswitch” was designed to erase itself upon completion.

With almost every piece of supposed evidence relating to this game leading to a dead end, it’s generally accepted that Killswitch is a myth by all but the most ardent believers. And there’s a reason why: “Killswitch” is also a short story by Catherynne Valente, a prolific but less than famous author of speculative folklore.

5. Bring Aeris Back To Life in Final Fantasy 7

Spoilers for a twenty-year-old video game: Aeris dies in Final Fantasy VII, after big bad Sephiroth stabs her in the back with a seven-foot long sword. Such was the grief that players experienced that they searched desperately for ways to undo Aeris’s death. Countless rumors spread detailing how you could revive her. Suggestions that her death was intended to be permanent were met with disbelief.

Some say a unique hard to find item could do it. Others said that the Revive Materia could be leveled up to such that it had the power to revive Aeris. None of the rumors were true, and some would resort to a Gameshark hack to bring her back at least in combat if not the story. In essence, Aeris’ death marked a pronounced level of grief and sentimentality on a level few games have ever evoked.

4. The Lara Croft Nude Code

As an atmospheric, puzzle-driven adventure, Tomb Raider was a revelation. Lara Croft became an instant gaming icon for reasons that had just as much to do with her appearance as it did her wisecracking, independent attitude. It was only a matter of time before someone would ignite imaginations of what she looks like under green tank top and extra short shorts.

The rumor goes that there was a secret code that would strip Lara down to her birthday suit. The code never existed, and not even assurances from the developers could stop people from trying or tricking others into thinking they got it. Many April Fool’s jokes have revolved around this gaming sex symbol, but the truth is that nothing short of third-party mods can get you a nude raider.

3. Curse of the Madden Cover

Becoming the cover athlete for the video game that represents the franchise you play for should be a major honor. But over the years it’s become a source of dread for fans and players alike. A so-called “Madden Curse” suggests that almost every athlete who has ever graced the cover of a Madden video game has either performed poorly or received an injury that takes them out of the season.

Last year, Madden 17 saw Rob Gronkowski miss the first two games of the season thanks to a hamstring injury. A groin injury took Donovan McNabb out in the ninth week of the season after appearing on the cover of Madden 06. And while Peyton Hillis was never a highly regarded athlete, his appearance on Madden 12 was followed by multiple hamstring injuries, forcing him to miss six games.

2. Blowing Cartridges

The common wisdom among children of the late 80s or early 90s was that the best way to get a game cartridge to work properly was to blow on it. The logic goes that by blowing on it, you get rid of the dirt and dust that keeps it from connecting to the console properly. Sometimes, you had to do it a few times more just to get it right.

But everyone did it, so it has to be true, right? Not so. The truth is that removing the cartridge for a good blow just gives you another chance to line up the connecting pins properly. Blowing, on the other hand, does more harm than good. Over time, so much impure air and saliva simply makes the connecting end of the cartridge rust.

1. Polybius

Legend has it that in 1981, a strange arcade machine debuted in Portland, Oregon. Described to be a vector graphics shooter like Battlezone and Tempest, the game became popular but players are said to have experienced many unpleasant side effects of playing, including amnesia, insomnia, and hallucinations. Then a month later, it disappeared.

It’s also said that strange men in black would visit the arcades, allegedly collecting data and observing responses to the game. Alas, it may have all been a publicity stunt for coinop.org, a fansite for coin-op arcade games. Professional skeptic and author Brian Dunning proposes that the legend may have grown out of early release version of Tempest that caused problems with epilepsy and motion sickness.

Which ones got you? Tell us about it below!