A modder who was working on overhauling Aliens: Colonial Marines discovered a massive issue that had a huge negative impact on the game’s notorious AI: a typo.

The Gearbox Software-developed title has been subject to some of the harshest criticism seen in the past five years for several reasons. Misleading marketing tactics, bugs, a lack of polish, and, most notably, near broken AI are at the forefront of these criticisms, and for good reason.

Remarkably, some of the AI issues—specifically regarding the AI controlling the xenomorphs—could have been remedied by the exclusion of a single letter.

Modder jamesdickinson963’s found a line of code that read “AttachPawnToTeather” which, obviously, included one to many a’s in the word “tether.” Removing this stray character vastly improved xenomorph AI by essentially telling aliens where and when to fight players.

Video game development is far from easy and takes a certain kind of magic to perfect, but hopefully this find will serve as a cautionary tale for years to come.

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