10 Best Enemy AI In Video Games

10. The Director - Left 4 Dead Series

Faceless enemies are the scariest of all, which is why, even compared to its creature collection of Tanks, Boomers, Witches and Hunters, Left 4 Dead's benevolent Director is a far more frightening foe. Intangible to players, Valve's aptly named AI acts as a guiding hand for the undead horde, endlessly crunching numbers and calculating possible scenarios behind the scenes, all in the name of variety.

Despite every entry in the trilogy having but a handful of static stages, no two attempts ever play out identically. Think you or a member of your quartet has a lock on where restoratives, ammo, or a nasty special Infected is lying in wait? No, you don't. The Director has already learned from your last tour on the merry-go-round what not to do.

Every choice it makes depends on your actions, down to health status, team skill, and location. These variables are never the same, nor is the path destined to unfold before you.

It's also a little-known fact that the Director has a sibling. Unlike its counterpart, which you should consider Left 4 Dead's game master, the other is responsible for dictating audible cues and soundtrack changes, making tweaks on the fly to deliver a bonafide, personally tailored experience.