Most Frustrating Boss Battles

[Springblossom]

Dullahan in Golden Sun: The Lost Age (I've yet to play Dark Dawn...I know he reappears there, but not sure if he's quite as frustrating in it).

There is nothing fair about this guy and he has no weak points. His HP is damn near the cap. He regens 200 HP each turn. One of his moves drains an additional 200 HP from between one and three of your party members. His Formina Sage attack can one-hit-kill pretty much anybody, but at least it only hits one person - he can also use Charon, the second-strongest summon in the game, at will, and it deals insane damage AND has a chance to OHKO party members (the strongest summon, Iris, is what Dullahan is guarding, so you can't use it against him). Oh yeah, and he has the most bullshit move in the game, Djinn Storm, which cripples your entire party's stats, makes you unable to summon, and cannot be blocked or evaded (and makes the Flash/Granite/Shade trick worthless).

To put it into perspective, Dullahan is so strong that he's actually not much harder on Hard Mode - his normal-mode HP is so close to the cap that it's only a small boost on Hard Mode, and his attack power is so high that he'll generally insta-kill you regardless of the difficulty level.

He's the only boss that I simply cannot beat "legitimately" (meaning no summon-rushing) - even Sentinel can be worn down with Djinn and the Sol Blade/Dark Sword, but Dullahan just murders me unless I spam summons from the start (and even then, he tends to take out half my team or more before he dies).

What a dick.

Oh, he's so much worse in Dark Dawn. You remember that one attack that uses your summons against you? He gets the ability to use that. I have no fucking clue how you're supposed to beat him in Dark Dawn, barring insane amounts of grinding.

 

[sm0t]

Boss I-No in Guilty Gear X2#Reload. She tends to break a lot of my combos, and her "Danger" attack takes out a good 50-90% of my health. I've only ever been able to beat her once, with Dizzy.

Raidou and Alpha-152 from Dead or Alive 1 and 4/5, respectively. Raidou was just crazy strong and copied moves from other characters. But Alpha-152 was fucking broken in the fourth game. Breaks through any combo, and her attacks often turn into mini-cutscenes that take out huge chunks of health. She's only slightly easier in the fifth game.

I remember being stuck on King Zing Sting in DKC2 for weeks when I was a kid. That damn parrot was just so hard to control.

And all Mortal Kombat players know that Shao Kahn cheap, but having only finished 9, I can personally confirm that he is a real son of a bitch in this one. You can literally only beat him by spamming. There is no good strategy.

I can vouch for this. I think Sektor was the first character I was able to beat Shao Kahn with, by spamming teleports to get behind him and getting as many hits in as I could before he turned around.

 

[Backwards Harvester]

The boss on the spinning sands of Contra III (second to last) Not only does it cause you to orbit the boss on the sand, you're going to have a hard time hitting " Eyerock" as I call it. The eye is the only weakness. That and dodging the serpent arms and fireballs it sends you. You have yo time your shots right or press L and R to hopefully lock yourself in a position to hit the eye. It is one of the areas the laser is actually super useful, if you can live long enough to lock yourself in position for a clean shot.

The ghost of Krow ( Donkey Kong Country II) This boss battle is a pain in the ass. You have to dodge waves of ghost birds and kill a solid one to get a barrel . If you miss you have to repeat the whole damn thing over. If you succeed you have to platform up while dodging the explosive eggs which will not only hit you from above but from the sides too. Thankfully, three hits is all you'll need to kill this hard boss.
DKCIII : Squirt ( the waterfall spirit/alien/rock creature ) This boss can't hurt you but he can kill you by using a water blast to push you to your death. It's very similar to fighting the third boss of Contra III This time it's water that moves in a rotating pattern instead of fire, but you have to keep moving and only have a brief window of time to hit him in the eyes.
Bleak, the robotic snowman: Donkey Kong Country III has bunch of different kinds of boss battles. This one is difficult but fun.
Barbos: The only underwater battle in the game. The water is red, as if someone slaughtered a bunch of cattle in it. The giant sea urchin only takes about five hits. But you have to deal with torpedo creatures and eventually the boss herself spitting out spikes that go outward from the center of the screen.

Mortal Kombat: Goro, Motaro, and Shao Kahn. Goro is slow but his punches and the occasional fireball will do damage. But it's when he renders you unable to move that he'll fuck your day up the most. He can pick you up with his lower arms and beat you with the upper two. Or he'l jump and stomp your face in ( In the original)
Motaro: I consider him worse than Shao Kahn. He only has two arms, but four legs gives him a speed advantage. He can trip you at a great distance with his iron tail, super punch you across the screen, or hit you with an energy blast. In addition to being gigantic AND fast, his defensive techniques are super cheap too. Scorpion's spear has no effect. Liu-Kang's fireballs will bounce back and burn him. Nightwolf's arrows are reflected, And using Subzy's ice will come back freeze him. Motaro migh also simply teleport behind you. Scorpion and Sheeva, as well as Sektor all have teleportation attacks that can help. Kano's blade uppercut works. and Jax has a few good combos to take him down.....
Shao Kahn is extremely frustration. But you can at least hit him with projectiles, spear, or freeze him.

Goldeneye:
Xenia ( 00 Agent mode) This bitch is a one-woman arsenal. She has an RCP90 and a grenade launcher. Since you're in the highest difficulty, there will be less body armor lying around on the way to the fight.
006: You've ruined his plans and saved the world from a disaster so you'd expect him to be pissed and have more weapons than Xenia. But No. He just has an AR33, and sometimes an occasional hand grenade. Also. you have to fight through the remainder of his soldiers. You'll be sorry if you ignore them. another problem, is that his weapon can hit you from a distance and packs a greater punch. Your gun isn't as good, but has a higher rate of fire, and due to the infinite enemies, you won't run out of ammo.
More to come later.

 

[Springblossom]

Bumping this because I just got past the Royal Rat Authority in Dark Souls II and holy shit that pissed me off.

The Royal Rat Authority himself is a rat the size of a bus. He's fast and has hugely powerful attacks, but that's pretty standard for this game. No, the problem is his flunkies, four little rats that spawn in the room with him. You get about five seconds to kill the little rats before the Royal Rat Authority himself climbs off his platform and jumps into the fray. If you don't kill the rats, you die. The rats themselves are fucking tiny and ridiculously fast, making it hard to kill them once they start running at you - and no, you can't lure them in one at a time, they all charge at you at once. Their attacks inflict Toxic. If you get Toxic'ed, you die; it drains health at an absurd rate and you won't have time to use an item once the big rat jumps down. If you try to block them, they'll chip down your stamina with their attacks on your shield, and then the big rat will punch through your defense and you die.

It's fairly telling that the first time I got the four little rats killed, the Royal Rat Authority himself got destroyed. I would seriously say that that was almost as bad as the Bed of Chaos.

Yeah, I went there.

 

[Springblossom]

One more Dark Souls II boss, then I'm done.

The Duke's Dear Freja. Being located at the bottom of Brightstone Cove Tseldora certainly doesn't help my opinion of it; I hate Tseldora and everything in it.

Freja herself starts with a horde of smaller spiders around her, and will bring more in if you take too long fighting her. She's a giant spider with two heads, one at each end, and an exoskeleton too tough to damage; you have to hit her heads. If you stay close to her heads, she tries to chomp you with her mandibles (which at least has a generous tell) or stomp you (which doesn't have a good tell, and her stomps are basically unblockable). She can also puke huge spreads of acid, sneeze webs that immobilize you, and has one horrible area denial attack where she stomps around with her legs and sprays vomit from both her mouths that basically makes it impossible to get in close. If you try to keep your distance, she can jump on top of you for huge damage or breathe a giant magical beam (because why not?). Said beam is completely unblockable, and I don't think you can roll under it either.

 

[Alec Benson Leary]

Speaking of Dark Souls, I'm going to mention the Bed of Chaos. Because even if it's a puzzle boss that only technically requires a couple of hits, the way the floor collapses around you it's basically just trial and error.

 

[Roger Rabbit]

Honestly, the only hard boss battle I have played in recent years is the Clocktower from Epic Mickey. You have to either thin out or paint his arms. If you thin it out, it dies. If you paint it, they become a platform so you paint it's face making it good again.

The painting is easier said than done, because it comes off if you take too long and it attacks again.

 

[c-no]

Boss I-No in Guilty Gear X2#Reload. She tends to break a lot of my combos, and her "Danger" attack takes out a good 50-90% of my health. I've only ever been able to beat her once, with Dizzy.

As a guy who played Guilty Gear in the arcade (Don't know which one it was but it could be the one you mentioned), I can agree with you. I-No is a frustrating boss. Only thing I'll remember is her victory pose at the end of fights.

 

[Dollars2010]

Adam the Clown in Dead Rising. I wasn't expecting there to be a clown in the game so I was caught off guard and had to have a friend beat him for me since I have a phobia of those things. I suppose he wasn't hard or anything just too spooky for me.

 

[Owlflaps]

There was Contra: Hard Corps. I remember that entire game was one boss battle after another.

 

[Springblossom]

The Mask of Infamy in The Binding of Isaac.

It's a boss version of Mask and Hearts, an already annoying enemy. The Mask chases you around, while the Heart runs away from you and fires eight way shots every time you get close. Normal Mask and Hearts die when the Heart dies, but you have to kill both parts to take down the Mask of Infamy. Killing the Heart is easy, but the Mask is another story. Do you have piercing shots, explosive tears, or lots of bombs? You can probably take it down with a minimum of trouble. Do you not? You're done for. The Mask has nearly perfect AI, making it ridiculously hard to get behind without getting hit. It's also fast enough to outrun your tears when it charges, meaning it's hard to fake it out and damage it. Even worse, for whatever reason, this boss doesn't have a health bar, making the fight feel like it's dragging on forever.