Toughest Robot Master in Each Game?

[MusashiAA]

MM1 - Between Elecman and Iceman: Both kill you in three hits with their projectiles, one fires a huge projectile and moves very fast, the other fires slow projectiles rapidly and are hard to dodge.

MM2 - Quickman: Not because he's powerful, but because he's superfast. Bustering this guy is always one of my highlights when playing MM2.

MM3 - Needleman: This guy is still unpredictable to me. Not only is he hard to hit with his weakness (which slows down the game, by the way), but his shots are very hard to dodge, and he deals a lot of damage with that hammer attack.

MM4 - RINGMAN: This guy's boomerangs are so confusing, thus hard to dodge, and the way the weakness interacts with enemies makes it a very uneven match...you could get a good match if Ringman jumps on the charged shot over your headm or a bad match if you can't avoid him at all.

MM5 - Gravityman: This guy is just plainly annoying to hit. You're constantly going up and down, and have to predict Gravityman's movement so you can damage him in midair.

MM6 (I think this game has very easy bosses, but if I had to pick one, I'd pick...) - Yamatoman: He's literally made of throwing you off.

MM7 - Freezeman: This is the pinnacle of boss fights. This is the master of Masters. It's not just a really intricate boss fight: it's duable AND hard.

MM8 - NONE. I'm sorry, weakness stuns are STUPID. If I had to pick one WITHOUT FIGHTING WITH WEAKNESSES, I'd pick Searchman...although I've never tried a buster-only run of MM8 myself, he looks pretty cheap. The hardest boss in this game is the first fortress boss...and it's a gimmick boss.

MM&B - Dynamoman: He recovers health and his lightning attack is hard to predict.

I haven't played MM9 or MM10 myself, but if I had to pick one, I'd say Galaxyman and Nitroman look like the hardest of their respective games.

[Kapus]

Galaxy Man is actually one of the easiest of the MM9 masters, alongside Splash Woman.

[CHAOS_FANTAZY]

Oh.  Hey.  This topic is alive again.  Guess I should update.

MM1:  I've learned to handle Ice a while ago; the only guy who still gives me trouble sometimes is Fire-Man.  Weaknesses or no, he is in general a pain to fight.
MM2:  Unchanged from Crash-Man.  Quick-Man probably deserves the spot more, but he's never given me as much trouble as good old Crash did.
MM3:  Unchanged from Shadow-Man.  It's been a long time since I've actually played MM3, and even though I've learned some of his tricks, he seems like more of a pain than the other RMs.
MM4:  I was probably overly frustrated at Dive-Man at the time of writing this because he killed me so much.  Ring-Man is probably the real pain here; I remembered beating him using his weakness and a small stack of E-Tanks the first time.
MM5:  Probably Wave-Man or Crystal-Man.  Everyone else's pattern in the game, I have down to a science, but Wave-Man can throw a wrench into that with his random Water Wave, and Crystal-Man has a large number of projectiles going for him.
MM6:  I really can't remember a lot about my MM6 experience, but I vaguely recall having trouble with Blizzard-Man.  Might have been his stage, though.
7FC:  Turbo-Man.  It was honestly a lot of stupid deaths, but this guy killed me more than any other 7FC RM.  The timing on his motor-car attack was really the only big thorn in my side.
8FC:  Search-Man.  Homing missiles in excess along with a hide-in-the-bushes gimmick was more than enough to make me dislike this guy, but then they threw in the scopes.  Dodging this guy has been one of my greatest challenges as a Mega Man gamer.
MM9:  I don't even know why I said Concrete-Man the first time.  Even with his weakness and a small stack of E-Tanks, I had trouble beating Plug-Man.  That guy is just a pain.
MM10:  No discredit to Chill-Man—I still remember all those kills you got on me in the boss room, bud—but after some reviewing, Solar-Man seems more difficult.  Similar amounts of damage, similar amounts of trickiness, but in Solar-Man, the boss room is also against you—the varied elevation makes for much more annoyance than ice physics.

RNC:  Clash-Man.  Wow, what a shocker.  He was basically a souped-up version of the Crash-Man I knew, with his new explosive detonating the entire floor instead of just one spot.  Failing to time my jump properly quite often, I met many an end against this foe.
4MI:  Shadow-Man Dust-Man was probably the trickiest RM here.  His randomized Recycle Inhaler made dodging a pain, and there were more than a couple embarrassing deaths where I was just sucked into him, turned into a -Tank, and kicked into a furnace.  I didn't get as mad at Dust-Man MI as I did at other tricky RMs, though—the mark of a really good boss, if you ask me.

Rokko Chan:  Fransiska & Lancea Rolling-Man.  Rolling is a lot like Crash in the sense that I seem to be the only person on the planet who has trouble with him.  I dunno.  I guess it's the projectile spam that gets me.  At least I can kill basically every other RM in the game with little to no trouble.
Christmas Carol:  Future.  Anyone who's ever tried to Dragon him will know exactly why Future.
Christmas Carol 2:  If we speak of Normal Mode, it's Want.  Want was the only one who really gave me any trouble on my first playthrough—Scrooge had some windup to all of his attacks, and Ignorance and Tim were basically "gimmick" RMs where once you learned how to hurt them, killing them was a breeze.  On Hard Mode, though, Scrooge gave me a lot more trouble because he kept healing himself, making him the hardest.
MMU:  Glue-Man.  Just...Glue-Man.  I could probably go start an entire topic about Glue-Man's bullshit.  To those of you who are content with that knowledge, advance.  To those of you that wish to know why, enter the spoiler below.

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Why not?  This guy's gimmick is basically half-piping back and forth across the boss room, firing a Glue Shot down at you every time he reaches one side.  He has perfect aim, and the boss room layout is designed in such a way that outmaneuvering a shot is frustratingly difficult, and if he hits you, it's a basic guarantee that he will collide with you and deal 8 contact damage.  ...Yes.  8 damage.  Of the many poor decisions MegaPhilX made in this game design, giving all of his RMs 8 contact damage was one of the worst.  So basically, since Glue Shot can't hurt you, this RM's basic damage method kills in 4 hits, and is more painful to dodge than Thunder Beam or Ice Slasher ever was.  Did I mention that he's half-piping back and forth really quickly, and might crash into you without landing a Glue Shot in the first place?  His weakness does half the damage of his basic method of attack and is harder to hit with; this should never be so!  If there's one thing MMU taught me, it's to never make a boss fight like Glue-Man's.

MMRevo:  I didn't find any MMRevo RMs particularly difficult—except for Storm-Man.  He stays out of range enough and his homing Storm Chaser does enough damage to make his peskiness notable.  Beat and some other weapons help ease the pain, though.
MMRF:  I think Photon-Man was the only Robot Master who ever actually killed me.  So I guess he wins by default.
Mega Pony:  Loyal Mare.  Mega Pony had its fair share of tricky boss fights (Though Magic Mare was unexpectedly simple and easy), but Loyal's struck me as blatantly unfair the first time I tried it.  Darting around her boss room and jumping randomly, she goes into her Sonic Rainboom charge attack whenever she nears, and...well, she just does a fair amount of damage.  She was basically Quick-Man, only exchanging projectiles for more damage.  She was very pesky, and it took me a long time to decipher a pattern for her.
Rockmen R:  Power-Man.  Rockmen R quickly sets up a precedent that hitting bosses with charged shots knocks them back in a manner similar to the way you do any time you get hit.  Then this guy marches into the room and smashes that precedent into a million pieces.  Being the largest RM in the game, jumping over his charging attack is difficult (Especially with RMR's wonky physics), and it does ludicrous amounts of damage on contacts.  If you're not a fan of that attack, his other one involves him pounding the ground and sending off a bunch of randomly arcing rocks, which are equally annoying to dodge but do less damage.  His weakness is the most clunky weapon ever, too—imagine Hyper Bomb with a much longer fuse and an explosion radius that's not even taller than Roll.  His only saving grace is that said weakness kills him in a sweet two hits.

[Shyster]

Heck, I actually feel like saying something about this

MM1: Ice Man. His projectiles do as much damage as Elec's, and they require precision timing to dodge. Thankfully his weakness kills him quickly. I don't find Elec Man too hard actually, but that's because I know how to pattern-lock him where he can't even fire off any shots!

MM2: Quick Man. Completely unpredictable, crazy contact damage and homing boomerangs that he's happy to blast shotgun-style right in your face. Even worse as a doc robot in MM3. Crash Man isn't difficult at all, just jump and shoot him only when you're about to collide.

MM3: Needle Man. Shadow Man is more predictable than this guy! Essentially undodge-able needle spam and quick jumps and the needle press that do insane damage.

MM4: Bright Man. He uses the flash stopper, you're going to get hit. And his weakness needs full energy to take him out. Ring Man still has a pattern that can be learned (jump twice over the first ring), and Dive Man can be dodged by well timed jumps if you predict his 3 charges. Just don't use the skull barrier.

MM5: Heck, they're all easy. Probably crystal thanks to sheer projectile volume.

MM6: Still all easy. I'll go with centaur because of his brightman-esque time stopping that makes the arrow split unavoidable. That and huge contact damage.

MM7: (FC): Burst Man and his insta-kill spiked ceiling. The fact that his projectiles block buster shots and his weakness is annoying as well. Slashman comes in at a close second thanks to his nigh-unavoidable slash dash off the walls when you're almost certain to be covered in the red slime.

MM8: (FC): Search Man. His attacks seem more suited to a Mega Man X game. There's too much to pay attention to and let's not even get started on the bullet wall that is crazy destroyer.

MM&B: Magic Man. How is he not mentioned more? Ridiculously fast movement and lightning quick projectile attacks that lead you right into his dashes. Way too fast paced.

MMU: Glue Man. Incredible potential for damage and getting stuck means you're dead in the water. At least it's not too hard to use his weakness when you remember it climbs walls.

MMxSF: Ryu. The spinning kick is unpredictable and he's invincible while performing it. Couple this with projectile streams blocking your shots and he becomes very difficult to hit.

[Dr. Crasger]

Hmm, the toughest Robot Master in each game you say?

MM1: Fire Man
Why Fire Man? He spams! It's a bloody spam battle if you want to kill this son of a bitch, the fact that the Robot Master rematches were one after the other didn't help, either.

MM2: Wood Man
If you tried him in Hard Mode, he was pretty tough. Then again almost none of the bosses in MM2 were actually a challenge, except Wood Man.

MM3: Shadow Man
Mega Man 3 brought me a bad time, the worst was with Shadow Man. I don't even get as to why he can slide, throw poison blades AND turn invisible.

MM4: Dive Man
That guy was too fast.

MM5: Charge Man
With or without Power Stone, this guy was tough.

I don't remember much of MM6. I have not played MM7-10 though.

[Jdude330]

Haven't played much megaman in a while, but I remember some terrible parts in stages to make up for this.
MM1: Elec man. This stage introduced me to the worst enemy ever. the thing that swings across the floor in hopes to murder you.
elec man himself is very hard, and if you accidentally do the pause glitch... oh gosh.
MM2:Quick man. my reaction when playing this stage: RUN! QUICKBEEMZ!!. quick man himself is hard without flash stopper, but, we know how easy that is to get. his speed makes him hard to dodge and shoot at the same time without a moonwalk code.
i don't know for MM3
MM4(MI): Wave Man/Enker/Dive Man: This entire stage gave me the most trouble. Enker is pretty easy, but getting to wave man isn't.
It took me AT LEAST 50 tries. Thanks save states! I had to go watch beed do it online before i could even get close! wave man Isn't too much of a pain, MM5 didn't give me any trouble. dive man's water cutter attacks are insanly hard to dodge, but can be fooled, his strange pattern got me killed several times.
MM10: Blade man. he would be easier if ALL THE WEAPONS WEREN'T TRAPS! Sorry, I just hate that game. his weakness is commando bomb, which will have you crying on the floor because you can never hit him. I tried him on EASY. He still killed me.

[Blizzardman19]

This is my list (Mega buster only):

MEGAMAN 1: Iceman: This guy is the hardest boss in megaman 1, his ice slasher is very hard to dodge and he can kill you with only three hits
Megaman 2: Quickman: He is very quick and had no AI pattern
Megaman 3: Shadowman: He moves a lot, and i don`t Know if he is going to slide or to attack with his Shadow Blade
Megaman 4: Brightman: He have a Pattern, but still very hard
Megaman 5: Chargeman: The same problem as Shadowman
Megaman 6:Tomahawkman: You have to be in the right spot to defeat him, he is very quick too
Megaman 7: Slashman: I hate when he climb to the wall
Megaman 8: Aquaman: Altough he is not very hard
Megaman and bass:Burner man: He allways kill me( except when i use the Ice wall)
Megaman 9: Plugman: His plug balls are very hard to dodge( you have to dodge Plugman himself too)
Megaman 10: Pumpman: I have a hard time dodging his water shield, in hard mode he shoots his boomerang too

Megaman unlimited: Trinitroman: If you hit the upper part of his head, he will explode( Thus killing you)

[Threxx]

Let's see...

MM1: Ice Man. Elec Man and Fire Man can both be tricked in to easy patterns, but you have to be legit with Ice Man. Dodging in between the slashers is very precise, and they kill you in 3 hits to boot. Talk about challenging.
MM2: Quick Man would be the obligatory choice, but Air Man gives me just as much trouble. We all know why Quick Man is hard, but some of Air Man's patterns are EXTREMELY precise and allow NO room for error whatsoever. I think both of them are equally difficult.
MM3: Shadow Man. This is purely a reaction battle, relying on reflexes to see what he'll do. My reflexes aren't always that great. You can see why this is difficult.
MM4: Drill Man. I've always had trouble telling where he's going to pop up, and his Drill Bomb spam can be a serious pain in the ass.
MM5: Wave Man. His random Water Wave plus the low clearance jumping his harpoons makes this the only hard boss in MM5.
MM6: Yamato Man. He sends spears everywhere, and he's pretty fast about it to. Having very little reaction time, and being able to block your shots, it's a challenging fight.
MM7: I've seen a lot of people say Freeze Man, but I've mastered him, so Slash Man. THOSE FREAKING JELLY ORBS. I hate them with an absolute passion.
MM8: I've never bustered the all of these bosses, but I'd have to say Search Man. The missile spam is really annoying to dodge.
MM&B: Burner Man, Dynamo Man, Astro Man, fucking every boss in this game is hard. Fuck this game.
MM9: Plug Man. Having absolutely no recognizable pattern, his jumping, his Plug Balls, everything is a challenge of wit and pure reaction time. It's kinda insane.
MM10: Commando Man. Having the ability to corner you for a nice cheap hit, and being all out insane as Mega Man, this boss earns his spot.

Hey, let's do fan games, why not?

Rokko Chan: Forest Man. His jumps are random, and dodging his homing bees just feels claustrophobic.
Mega Man Rock Force: Judging on the recent update, Charade Man. He went from being mildy challenging to absolutely insane. Bullets and projectiles fly everywhere, and combined with the Charade Clone, it just gets ridiculous.
Mega Man Unlimited: Trinitro Man. Being able to corner you easily to hit you with the powerful Nitro Blast, having the gimmick of his glass case, makes this a seriously challenging and tense battle.
Mega Man Revolution: I find these bosses to be particularly hard (and cheap in some ways), but Storm Man and Cyro Man would have to be the worst for Mega Man and Bass respectively. Storm Man is constantly out of your reach, and Bass' weak buster makes killing Cyro Man in time impossible.

[Beaver]

Sweet goshdarn lord, Dr. wilys machine on NORMAL. ON POWERED UP.
also theres yellow devil, and honestly, i'd say my biggest RM struglle was mostly guts because of his stage, and Elec for hard boss.

[Metallix]

doing this aGAIN BECAUSE I'VE ACTUALLY PLAYED ALL THE GAMES NOW GUYS

MM1

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TOUGHEST RM: FIRE MAN / ELEC MAN
Dead tie. The former has hardly any tolerance for mistakes with his constant and somewhat random attack pattern.. One mistimed jump and you're literally toast.
The latter is just an utter douche with no respect for newbies whatsoever. I cried myself to sleep that first night.

EASIEST RM: BOMB MAN
First bot that I ever beat, by now the fight with him is short and sad to watch. >_>

MM2

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TOUGHEST RM: AIR MAN
Fragging hell, the tornadoes everywhere. Doc Robot Air is much easier to tolerate with MM3's slide, but I was never great at making precision leaps like that.

EASIEST RM: FLASH MAN
What. A. Joke. Even without the all-powerful Blades, Flash is slow, deals very little damage with his main attack, and is an easy first target. Bubble Man at least presents a challenge when buster-running with a spiked ceiling and lots of bullets. All Flash can do is hope that you get caught on a ledge and he can collide with you.

MM3

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hardEST RM: HARD MAN
Haha yeah. Screw this guy. Even his weakness does the barest amount of damage. One of the only bosses in the entire series that requires an E-Tank.

EASIEST RM: MAGNET MAN
For shame. One of the most potentially powerful Wilybots in the series can only get a few cheap shots in with a missile before getting the electrocution of a lifetime. Power Fighters gave him a few neat tricks, but Mags has yet to be done any justice, in my opinion.

MM4

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STUPIDLY TOUGH RM: BRIGHT MAN
One would think this would be Flash Man all over again. Hnnnng, no. Bright Man will hit you when you get flashed. There is no dodging his attacks, whether its just a buster shot or a full-on fatboy tackle.

EASIEST RM: PHARAOH MAN
Disappointing, just as Magnet was. Still a decent fight when he gets a lucky hit while jumping or using his Pharaoh Shot, but he's very predictable.

... I no longer consider Toad Man a boss in this game, by the way.

MM5

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TOUGHEST RM: CRYSTAL MAN / CHARGE MAN
Charge Man gets a spot mainly because his attacks are difficult to dodge, and I always get caught off guard when he decides to turn around and walk into me. Hnnnnng.
Crystal is just... annoying. I've never played those Touhou/"bullet hell" games, but my impression is that it's a lot like this.

EASIEST RM: STONE MAN
Long, boring and tedious fight. So much so that I'll even lose focus and get smacked with a boulder and start making stupid mistakes. This is just poor boss programming, really.

MM6

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TOUGHEST RM: WIND MAN
I've never been able to beat him without his weakness. Like... ever. I'll either get trucked in midair or try to get fancy with that gyro attack. It's just... hnnnng.

EASIEST RM: KNIGHT MAN
Just like Stone Man, but not nearly as long. I get cocky sometimes and take a spiked flail to the back of the head, but besides that, I can easily no-damage Knight.

MM7

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TOUGHEST RM: JUNK MAN / FREEZE MAN
Junk is a lot like Charge Man, to me; his attacks are big and hard to dodge, and they do a lot of damage. Aside from that, he's predictable and doesn't get this title by much; most of the 7th Gen is actually quite easy.
Except Freeze Man. Dear god, what an asshole.

EASIEST RM: BURST MAN
bblz bblz bblz bblz bblz
He'll get annoying sometimes with those bubble traps, but he could be so much better than this.

MM8

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TOUGHEST RM: ASTRO MAN
I can't. I just can't. Can you. just. hold. thE. F*CK. STILL.

EASIEST RM: FROST MAN
Meh.

MM&B

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TOUGHEST RM: GROUND MAN / BURNER MAN
Essentially Drill Man with spread rune, I guess, but so much worse than that.
And Burner tends to be HELLO IM GONNA BE HERE NO IM HERE HEY HERES FIRE OVER HERE NOW WHEEEEE

EASIEST RM: MAGIC MAN
He was once the most annoying shit ever. Imagine my surprise when I figured out how to brutally murder him before he could get a shot off. HNAAH

MM9

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TOUGHEST RM: GALAXY MAN
As with MM7, I don't find these guys too difficult anymore. Galaxy earns this spot just because of the sheer rage I endured just trying to land a hit on him, a'la Astro Man.

EASIEST RM: TORNADO MAN
Meh. His attacks are hard to dodge, but they don't really do much.

MM10

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TOUGHEST RM: BLADE MAN
ohey i dodged your blades lolol what are you going to do now
*whoosh* WHY HELLO THE- *dead*EASIEST RM: COMMANDO MAN
He's rather predictable, once you time your jumps over the shockwaves properly.

Also these because I don't know why we're doing these now

MMxSF

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TOUGHEST BOSS: VEGA / CHUN-LI
Vega is obvious. He's just as annoying as in Street Fighter itself, if not moreso.
Chun-Li always seems to catch me in midair with a kick to the nuts. Always.

EASIEST BOSS: BALROG
Aside from not knowing what I was supposed to be doing the first few times, Balrog was pathetically easy and it's hard to actually die now.

MMUnlimited

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TOUGHEST RM: well uh
goddamn this game is hard I've only ever beat Nail Man once.
EASIEST RM: asdgflsgafl
go to hell Rainbow Man

[Threxx]

doing this aGAIN BECAUSE I'VE ACTUALLY PLAYED ALL THE GAMES NOW GUYS
long post

I love the irony in the fact that you can defeat Pharoah Man easily but have trouble with WIND MAN? Seriously, he might be the easiest boss in all of Mega Man. Just know that you can always jump the gryos, no matter what position they're in.

[Metallix]

The thing is that I tend to freak out the first time I enter a boss room. I have been killed by almost every RM at least ten times before I can start to figure out their pattern and can calmly approach them and eventually work the fight down to a science, as I'm sure most long-time players have.

Bosses like Wind and Crystal, on the other hand, have an element of chaos to their fights with either lots of projectiles or ones that move in nonsensical ways. The urgency I feel when first fighting the boss never leaves because you have to be constantly moving to avoid them, and with how quickly Wind can use one attack after the other, the freakout is inevitable. To avoid that, I never face him first and grab his weakness. I've just never taken the time to approach these guys calmly.

That and MM6 was generally pretty easy otherwise. Aside from having no quick select with such a large item selection.

[<geminibro>]

Blade Man from Megaman 10. Just Blade Man.

Plus, the Commando Bomb controls like fish sticks, so yeah.

[Oliver]

MM1: Bombman.
MM2: Everyone is easy.
MM3: Geminiman.
MM4: Drillman.
MM5: Chargeman and/or Crystalman.
MM6: Centaurman.
MM7: Freezeman.

SFxMM: Almost all are easy.
MMU: Trinitroman.

[Sphotof]

MM1: Elec Man.
MM2: Quick Man. He won't even give me a chance to hit him.
MM3: Shadow Man
MM4: I remember Pharaoh Man and Ring Man being annoying.
MM5: Charge Man.
MM6: Eh,  I don't remember very well. Tomahawk Man was annoying.
MM7: Slash Man
MM8: Search Man
MM9: It's been so long. I can't say.
MM10: Commando Man
MM&B: I don't remember much of Dynamo Man, so Burner Man. I HATE him.
MM&B(WonderSwan): Every boss was hard, so I can't say. Not counting the last boss, I remember Doppler Man being annoying.