Typos are something that we all have made at some point in our work. When it comes to publications, typos sometimes let loose the trolls, sometimes they are flat-out embarrassing, and sometimes they result in both. With that said, we feel for the programmer who wrote code in the critically-panned 2013 game Aliens: Colonial Marines.
The programmer made a single typo which was largely responsible for how bad that game sucked. Anyone who was a fan of the movie franchise the game was based on wanted this game to be awesome. The problem was that the Aliens in the game were brain-dead because of this single-character typo.
A modder dubbed jamesdickinson963 has been tinkering with the game in an attempt to fix its flaws and found the coding error that references the game's tether system that assigns commands to AI characters. Rather than correctly calling out "AttachPawnToTether" it instead is written "AttachPawnToTeather", so no commands are assigned to the aliens allowing them to walk right past you without trying to punch their mouths into your chest.
Jamesdickinson963 made a new and improved version of the game dubbed TemplarGFX's Aliens: Colonial Marines Overhaul and says that he found the typo in a configuration file called PecanEngine.ini. That file was supposed to give the Xenomorphs in the game their location, define their fighting space, and tell them where the exits are. Granted the game was rife with other issues so the entire blame can’t be laid at one person's feet.
When you know what you mean to write, it’s often harder than you think to find errors in your own work. A personal example is when I once wrote a story about the Large Hadron Collider, only I missed in the title that the "R" and the "D" were swapped in "Hadron" and wrote a headline with an entirely different meaning. It was almost worth it for the comments alone.