Maybe “fix” is wrong. More like “improve, kind of, but not much because the game is already more or less irredeemable for a number of other reasons sooooo”, but that’s too long for a headline. Anyway, apparently a misspelled word in the code defining the game’s AI behaviour had broken it completely, and the real lesson is that making games is much more complicated than you think, kids.
Prompted by a recent Steam sale on Aliens: Colonial Marines, a user on the ResetEra forum recommended installing TemplarGFX’s ACM Overhaul mod, claiming it “makes a huge difference with how the game looks and plays”. In a subsequent discussion, another user pointed out that in 2017 the mod creator had discovered a reference to a “tether” in one of the game’s .ini files, which assigns AI commands, was spelled “teather”. The results were, uh, somewhat less than optimal for the game’s grossly incompetent AI.
“When a xeno is spawned, it is attached to a zone tether. This zone tells the xeno what area is its fighting space and where different exits are. In combat, a xeno will be forced to switch to a new tether (such as one behind you) so as to flank, or disperse so they aren’t so grouped up etc.,” he explained on the mod’s page. “Whenever the game tried to do this, nothing happened. Now it does!”
So, that’s awkward. But is it so uncommon? This was obviously a bug with very conspicuous results, but every game ships with bugs. I suppose you could even describe post-launch support and update development as a sort of… bug hunt. Anybody? No? Okay.