Hmm... this thread isn't too old, I think it's safe to bump it. 
OK, this may not be the dumbest AI in the world, but this is a contender. I was sorting through my older games and came across Lord of the Rings: Return of the King. Well, I tried it out, found a few AI stupidities, and thought of this thread.
OK, it seems the ROTK AI has a weakness when it comes to ranged weapons. The ghost-thingie you see highlighted in green is an undead archer. He is greenish because I have my bow pointed at his head. He's right there, but seems content to just sit there, and not even fire. I waited a minute before firing, dispatching him instantly.
Kinda depressing.
Oh, another game that has a mindless AI is Star Wars: Knights of the Old Republic I and II. The AI runs as fast as you, so you can hide behind counters and they will be stuck, even though they'd reach you if they went to the right about a game-foot. I stand back and drill Dark Jedi with blasters, a very funny sight.

OK, this may not be the dumbest AI in the world, but this is a contender. I was sorting through my older games and came across Lord of the Rings: Return of the King. Well, I tried it out, found a few AI stupidities, and thought of this thread.
OK, it seems the ROTK AI has a weakness when it comes to ranged weapons. The ghost-thingie you see highlighted in green is an undead archer. He is greenish because I have my bow pointed at his head. He's right there, but seems content to just sit there, and not even fire. I waited a minute before firing, dispatching him instantly.

Kinda depressing.
Oh, another game that has a mindless AI is Star Wars: Knights of the Old Republic I and II. The AI runs as fast as you, so you can hide behind counters and they will be stuck, even though they'd reach you if they went to the right about a game-foot. I stand back and drill Dark Jedi with blasters, a very funny sight.