Remember they also kicked down objects to use them for cover.iggyus said:Enemies were pretty fucked up in F.E.A.R. They always flanked, tried to get behind you, threw grenades and used some brutal team tactics. It was impressive.
That said, FEAR or UT is most likely it.
Unless this thread counts fan-made AI mods, in which case there's this one Starcraft AI mod that was downright impressive - played almost like a real person. Can't recall the name of it though.