Whats the worst/most hilarious game AI you have encountered?

I booted up Sonic 2 today for the first time in aaages, and even though it was made over 10 years ago, I still find how bad Tails' AI amusing. Especially when the little runt drowns. Its not that bad for its time, but it got me to thinking of the games with the worst AI. Personally, fucking Jung from Rainbow Six Vegas (BITCH ALWAYS SEEMS TO BE RELOADING), and I remember Cod wow being pretty bad.

Fifa 11 has some really, REALLY awful AI. 
 
I actually can't describe how irritating it is. Basically, imagine all the basic functions a certain position must carry out. Now don't do them. In fact, if you aren't player controlled, you won't chase the ball, and if it runs past you, you may even back up a few steps. 
 
That and oh-so-much more.

I definitely remember a lot of times in cod when you'll be behind cover and you ai buddies are just standing there blindly firing, but thats not funny.....

I once played some random RTS i can't remember the name of. Besides it being extremely slow and unbalanced, the units more or less didn't react at all. I played it agains a friend of mine on LAN, and we had to give up, we couldn't kill each other, seeing as selecting 10 or more units, only around 5 would actually move when prompted, of those only around 3 would move the right way! The rest would simply stand there. The result of this was, that only a few of the units would actually reach the base, and get utterly destroyed by completely overpowered defense cannons. Oh, and unit's left in places of the map you didn't look at would dissapear.

Your squadmates in both Gears games seemed to have fucking awful AI, some of the worst in my recent memory. I can't remember all the times when I got downed for some reason and they charged right the fuck past me into battle instead of reviving me.

• Halo Reach, Noble members really don't like to shoot much. It takes me out of the story entirely seeing them dumb as statues.

• Monster Hunter Freedom Unite. Not so much bad A.I.  but your cat companion will never cease to mew during a hunt. Mew, mew, mew... You'll know when I play MHFU because of the endless cat noises coming out of my PSP. It's hilarious how kamikaze these cats are though, jumping into fireballs and laser beams and what not. Hell, some cats run into monsters with exploding barrels (it's a feature, not dumb A.I.).
  

• Left 4 Dead 1-2. A.I. dudes shoot well enough but always slow on their feet to follow you. Also, they don't know how a finale works, RUN TO THE GOD DAMNED ESCAPE POINT!
  

• Street Fighter 4, Zangief spinning lariats break the game A.I. apparently. Just spam it on the hardest difficulty and it's an automatic win.

• Sacred 2, during escort quests the NPCs usually don't fight but run... into other enemies and monsters. I've given up hope on doing a lot of them. Thankfully the game developers knew this problem and made story related escort NPCs invincible. If they knew it was a problem, why add them in the first place?

Why don't my AI controlled team mates in L4D2 pick up Melee weapons? This is a massive fail.

L4D2's friendly AI is fucking abysmal, but I've gotten some good laughs out of it. There have been countless times where I have been getting pounced on/strangled/crushed, etc. and they will literally just stand right next to me and do absolutely nothing. Sometimes they won't even help me up after I'm downed and will occasionally just run away afterward. It's infuriating when you're seriously trying to play the game, but kind of funny any other time.

I was playing Sakura Wars: So Long, My Love and I was on the last 'chapter'. The last chapter is comprised of nothing but a gauntlet of boss battles with some save spots thrown in because otherwise it'd be ridiculous. 
 
However, my first few times playing it, I never got past the first boss battle, but not because I kept dying. The first battle is a combination of air and ground and the air enemies don't move like the ground enemies do. In that the air enemies tend to move in a straight line or up and down and the ground enemies can move in all directions. I don't know how it happened, but two aerial enemies managed to vertically stack on top of each other, or close enough so nothing could pass between them. That didn't stop the next enemy from trying. He could only move horizontally and ran straight into the stacked enemies. Since he wasn't moving, his move meter never went down so I was stuck watching this incompetent robot push at these other robots to no avail, all the while the screen is shaking. 
 
I restarted the mission and this same thing happened three more times. 
 
On the fifth time I made a point to take out any enemies that were a bit too close to one another. 
 
 That was the only problem I encountered with the game and it came at the worst time.

Dead Rising and Left 4 Dead stick out the most in my mind.

I played Halo 3 (for the first time) wih a friend and jumped aboard an occupied vehicle. The AI then proceeded to slowly drive off a nearby cliff. 

Also obligatory Radiant AI vid:

Halo 2 
 
Kept me off Halo for years until I played Reach at a friends house.

  The operation flashpoint/Arma series has some pretty bad AI at times. 
 
But then again, its probably some of the most powerful AI Ive ever seen in a game too, as the can accomplish some pretty complicated  stuff in the free sandbox that is Arma.

Most hilarious AI I have ever seen?  My pick is Far Cry 2.  Now don't get me wrong, I LOVED playing and beating Far Cry 2; it was one of the most enjoyable, entertaining and satisfying games I have ever played.  With that being said, the AI could sometimes stir up a nice laugh.  And not only on my part.  My fiance doesn't play a lot of video games and when she would walk by while I was playing the game, she would notice that men I had just killed had body parts (arms, legs, heads) that were flailing around uncontrollably.  Sure, it probably does not sound funny, but it is definitely amusing when you are watching it.
 
Wait a second...I may have not described the AI at all, just the programming of the game.  Whatever.  Far Cry 2.  That's my final answer, Regis.

" Your squadmates in both Gears games seemed to have fucking awful AI, some of the worst in my recent memory. I can't remember all the times when I got downed for some reason and they charged right the fuck past me into battle instead of reviving me. "

Medal of Honour on the hardest setting...........punching a guy in the face who's holding an M60 and looking straight at you is unforgivable AI.

I utterly despised the Reach AI. Apparently the elite Noble team members never took driving courses and so you're always forced to have a human at the helm. Not my idea of fun.

Just Cause 2's bad guys reminds me of the bad guys in Commando. Stand still, shoot and hope for the best.

Idk if this counts but the most annoying AI I've encountered is the narrator in Crackdown 2. Towards the end of that game I had mute the sound because he was still saying the same shit from the 1st hour of that game. Fairly annoying, at least in my opinion.

Any NPC in either of the Dead Rising games.

Anyone remember the Darkest of Days quick look? nuff said.

Every single NPC in Red Dead Redemption deserves to be shot.

Worst AI I've seen would be forza 2. It seems like they don't even see you some times and will hit you taking both of you out of the race. 
 
On the other hand, I've been playing Uncharted 2 and that AI is quite good.   
 
They often, much to my chagrin, sneak around behind me of flush me out of cover with grenades.... and they do it well. 

" Any NPC in either of the Dead Rising games. "

" Every single NPC in Red Dead Redemption deserves to be shot. "

The first Empire Earth game and it's expansion were ruined by the AI being a retarded, cheating mess. It would constantly get resources just out of the blue, always know where all your units and buildings were located at, build a shitload of defensive towers all around the map, instantly detect any hole in your defense and probably the worst offender was that it could build and send military units after your base way before humanly possible.
 
On the other hand though it would not tech up until after you did the same, it would create a ton of just ONE unit type at the beginning of the game, it would plop down buildings seemingly at random and sometimes it would not move it's units even if they were being killed by a bunch of dudes.
 
In the end it always went down to something like defeating the initial rush by the AI and then nothing would happen until you explored the map and found some of it's building, in which case it would attack.

" The first Empire Earth game and it's expansion were ruined by the AI being a retarded, cheating mess. ..."

I can't think of any games off the top of my head that have had decent AI.  It usually seems like it was just an afterthought.  Gears 1 and Gears 2 were pretty bad though.  The friendly and enemy AI.