I think people just haven’t played Eternal Champions to find out how fucked up that game is…
Super Ghouls and Ghosts
Yeah pretty much all SNK bosses(including the metal slug games).
CvS2 - O. Rugal (Without ratio or a top tier)
ST - (US ver) arcade(highest difficulty setting)
KI(SNES)
Gouki mode was a Bitch!
I didnt read it all but I say MK2 and Ill cite 2 interesting things to back this up.
1, The cpu always seems to throw you if you try to through, to the where I played one where you could freeze the AI with SubZero and if you throw them, the AI still throws you while they are still blue, clearly indicating they are frozen.
2. Spam Shang Tsung fireballs like crazy, the cpu will duck under them. If you can keep streaming the 3’s in a row, they will stay crouching, After 15-20 secs the cpu will magically glide across the floor while still crouched, and uppercut you. Especially Baraka from what I recall.
Meanwhile if you played on player 2 side as Shang Tsung you could jump back, kick and ai would slowly walk up, jump forward kick and it would stop and eat the kick. All the way to Shao Khan.
Art of Fighting 2. The only game where you can’t get by the first opponent. After that Any of the MK games, specifically UMK3. I played UMK3 through Mame to get a feel for Mk after having not played any for so long. So I picked it up, set the difficulty to Noraml and was having fun with the Autocombos until the 3rd Opponent. The Computer reads your button input and perfectly counters everything you do and can do air grabs free. I set the difficulty to the easiest. And the first 3 opponents were pretty easy, then the input-reading A.I. kicks in and utterly destroys me. What a coin hog lol.
ST is another one, even on the easiest difficulty it reads button input and destroys you.
I love sitting down and playing through Tetris Attack on the SNES set to the hardest difficulty (the hidden one). Just did it for 'prolly the 100th time last weekend 
Final Fantasy tactics 1.3 was the only game I had to think to win on.
Still can’t beat the vampire lucavi boss in the cemetery. That was fuckin impossble without elixers or exploiting the blood suck status.
I could never get past the first character as a kid 
Oh, and Goenitz in SvC Chaos…fuck him.
Parace L’Sia, AH2 version.
See [media=youtube]hjUa_TY1xgc[/media]
any snk boss…but the boss from samurai shodown 6. once he gets on his flaming horse, its over! its not that his horse riding super automatically breaks your sword or takes 50% of your health meter, but that the attack practically takes up the entire screen.
impossible to avoid. and when he’s just got his flaming spear, he still has too much reach and speed.
the rumble fish’s ai is pretty hard just on easiest difficulty setting. i still can’t unlock all the characters since you gotta beat story/arcade mode from start to finish without using a continue…can’t do it. even on easiest difficulty…ai still blows u up.
igniz did an infinite on 2 out of 3 characters last time i played kof2001 back in the day.
i’d have to say, MK 2. Seems nearly impossible to beat on hardest setting.
KOF final bosses. OH and flame lurker in demon souls. The 1st time fighting him he will kick your ass, it took me like 5-6 trys to find out there was some glitch to beating him
Super Turbo last revision BY FAR.
I can beat MK2 and UMK3 in one sitting, but ST is a whole other level of frustration, IMO. Each character has a whole toolbox of rule-breaking moves that are impossible to counter.
Just play the Japanese version (Super X) then go back to Super Turbo, the difference cannot even be measured. If you want to play a cheating computer, play ST.
Art of Fighting 2 and Virtua Fighter 2 AI reads inputs and beats your ass 90% of the time, but it can be cheesed to some degree (with a little luck).
I would place vote for TMNT:TF on the Genesis as well (hardest mode). If you even took one throw from the opponent, be prepared for the possible infinite throw loop (and yes, tried to test with save states… it’s inescapable).
At best, you can exploit some things with the dumb design choices made (+ on block specials from April)… but for the entire cast, that might be to hard.
There is another way to exploit this though… just press 2-player start and beat the opponent, and it counts as you winning against that character in single player =D
Mortal Kombat 2 had sweet spots with sweeps that can be pulled throughout the game. Against Kintaro, I believed there was a sweet spot in the corner where you can just Jump Back Roundhouse. Just make sure you got him to walk first (in case he does the unblockable stomp). If he stays still, you can jump twice in probably hit him out of his stomp move if spaced right, or whenever he’s standing still if your jump attack hitbox is big to hit him. Shao Kahn I had memories of Standing Low Kick and jumping attacks. There were definitely some exploits you could try for every character.
Hard mode MK2 def had exploitable spots, more than MK Trilogy. You could get jump kicks for weeks if you were positioned at certain angles, and the AI wouldn’t even counter projectile in the air or nothing. You could also flip back and sneak in roundhouses when the AI flips forward, but for some characters it didn’t work all that well (Scorpion, Rayden, etc.) because they would be programmed to projectile.
Wow… the bumps are real.
Anyway, I agree that MK2’s AI really did cheat, and was blatant about it. I was going to mention how in one of the older versions it wouldn’t even let you throw a frozen AI opponent until someone else did. It’s just so funny to see it prioritize cheating you so hard that it causes palette issues for the AI character.
But, as of Revision 3.1, it IS possible to 1CC the game. I left a basic guide in this thread much earlier, but here’s some character-specific strategies for 2nd match on.
All characters except Shao Kahn/Kintaro:
- Will do a seemingly random special at about starting range.
- Will always perform a specific counter when you jump in on them, depending on range.
- Universal action for your jump-in is a roundhouse (B+HK) if at sub-optimal range for their character-specific punish.
- All characters will neutral-jump HK if you try to jump in from the corner.
- Easiest character to 1CC with is Scorpion. Time a single AA HP for most damage, then follow with Teleport Punch (QCB+HP), Spear (B, B+LP), uppercut (D+HP).
- If they walk close enough, contest space with a sweep (B+LK). If you connect, you can walk forward and start a jump-away to bait them into jumping in return.
- ‘Death Punch’ is an AA HP that pushes you backwards. Only Scorpion can combo after this.
- After any uppercut, start a jump in when they touch the ground, and time a kick to graze their hitbox on wakeup. This is the only time you can jump in for free.
Liu Kang:
- Jump-in action: Air fireball. Don’t jump in.
- Duck and block at beginning of round. He may bicycle kick at the start, leading to a free uppercut.
- Slightly higher jump than other characters except Kung Lao (the ‘shaolin arc’). Adjust death punch timing accordingly.
Kung Lao:
- Jump-in action: Hat toss. Can stuff.
- Duck at beginning of round. If he teleports, free uppercut. If hat throw, you might be able to block and punish with Spear-Uppercut combo, but timing is tight.
- ‘Shaolin arc’ jumps.
Cage:
- Jump-in action: High fireball.
- More ducking at start of round. Shadow kick means a free uppercut.
Reptile:
- Jump-in action: Acid spit. Can stuff sometimes.
- Annoying character. If he vanishes at the start, use raw teleport punches to bait a block. Better to eat a single punish than throws to death.
Sub-Zero:
- Jump-in action: Ground freeze. This one is trivial to beat out.
- Fairly simple to defeat. No good punish opportunities, but easy to bait into jumps.
Shang Tsung:
- Jump-in action: neutral-jump HK. Whiffs fairly often due to wonky hitboxes.
- In normal form, not too threatening.
- Treat transformations like the actual character and adjust accordingly.
Kitana:
- Jump-in action: Fan Lift -> Square Wave combo. Never jump in.
- Total cunt. Thankfully, death punches are easier to land on the female ninjas.
Jax:
- Jump-in action: Air throw. Don’t bother.
- Duck at start to avoid projectiles. Just eat ground pounds in the start of a round, or walk in a little to get him out of special range.
Mileena:
- Jump-in action: Air sai. Don’t bother.
- Block at start of round. Roll and teleport kick can be blocked and punished.
- Punish blocked roll with death punch combo.
Baraka:
- Jump-in action: Blade fury. Can be baited, but spacing is tight.
- You want him to throw projectiles. You can actually sweep him from his outstretched blade. Thanks, hitboxes!
Scorpion:
- Jump-in action: Spear. Can be beaten, but spacing may be off if you try to fight him like Smoke or Noob due to slower walk speed.
- I’ve never seen teleport punch or leg takedown used by the AI, so fight him like a slow Smoke.
Raiden:
- Jump-in action: Electric bolt. Can be stuffed, but a little more difficult.
- Has Shaolin Arc jumps.
- Annoying to deal with, as torpedo is tough to punish.
Smoke/Noob:
- Jump-in action: Spear
- The only real threats in these matchups is their defensive and offensive stats. They for sure take less damage; not sure if they hit a little harder too.
- Smoke has a run button before it was even a thing. He can rush in to throw you, and if you don’t react in time, just eat the damage and take a position reset in your favor.
- Both will almost always throw another spear if you happen to get tagged by a Spear-Uppercut combo of theirs. You can spear back as theirs whiffs for free damage and positioning. You’ll lose the raw damage trade, but might win on followup damage.
Jade:
- Jump-in action: Fan throw. A slow startup move, so you can easily stuff her.
- She is always projectile-immune here, so death punch and follow up with teleport punch, but move back and get in range to jump in on her wakeup.
- She’s also more durable, but this shouldn’t be a problem, since you can easily get a lot of corner carry with a jumpkick pattern. Flawlesses should be very possible here.
Kintaro:
- All rules go out the window here. He might try for uppercuts that whiff with the right jump spacing, but don’t bet too much on it.
- After a telestomp connects, he will always move toward the center of the stage on rebound and taunt (roar). Free damage, but you lose this trade hard.
- He does have an exploit, but it requires him to be cornered. Stand just outside of HP range and mash HP. He will just walk into it repeatedly and die for free. Difficult to set up consistently.
- Best pattern is jump in with a kick, and then immediately jump back and stick a kick out to keep him blocking.
- low vertical jump doesn’t actually do damage, and is usually followed by a low forward jump. More free damage.
Shao Kahn:
- Block at the start in case he tries a spear, then back off into the corner.
- Block in the corner, and uppercut after every shoulder charge.
- After an uppercut, jump in to tag his wakeup with a kick and jump back.
- If he taunts in your face, spear him.
- Very difficult to actually lose unless he just never shoulder charges.
This is how I always beat him. Was it changed in later revisions so that it’s more unstable?