10 Genius Ways Video Games Fixed Their Own Mistakes

2. A Player Name Glitch Inspired The Spy Class - Team Fortress

Spy is one of Team Fortress' most popular classes, given his ability to turn invisible, feign death, and even disguise himself as any class on either team, allowing him to easily murder unsuspecting enemies.

But Spy's genesis dates back to the original version of Team Fortress, which was of course a mod for Quake.

During testing, the dev team discovered a glitch where a player's name would randomly appear in the incorrect colour, implying that they were on the opposite team.

The bug was fixed sharpish, but this planted the seed of what would eventually become the Spy class, noted for his penchant for confusing the opposing team as much as possible.

Spy remains a fan favourite class two decades later, no doubt in part because of another mistake that made its way into the follow-up, Team Fortress 2.

Spy returned in his shinier new form (pictured above), but a glitch allowed players to perform a bizarre and hilarious walk called the "Spycrab", by equipping the Disguise Kit, holding down the crouch button, looking up and walking forward.

The absurd results speak for themselves, really.

The glitch was beloved enough by fans that Valve didn't have the heart to patch it out, and over a decade after its discovery, it's still in the game.