Mega Man's original crowning moment of awesome was defeating the six robot masters and Dr. Wily for the very first time. To make it even more awesome, this was before Energy and Weapon Tanks. Mega Man was, like his sister Roll, originally designed as a housekeeping robot.
Beat being able to take down anything with ease in 5 and 6, so much so that his function was completely changed from 7 on.
In Megaman 7, if you time it right you can defeat Turbo Man and Spring Man with Noise Crush as their health bars begin to fill up.
Mega Man: I am more than just a robot. DIE, WILY!
Oddly, Rockman never says those words in the Japanese version of 7, meaning this was originally Wily's crowning moment. He told him that robots can't harm humans. In the American version, he said the above line. In Japan, he obediently powered down.
Bass trumps them both right afterward by compressing a Breaking Speech into a single phrase:
The moment in 8 where Duo takes out a huge mech Wily built singlehandedly, made even better when he cuts the freaking robot's face off, was awesome in it's own right. Keep in mind that this robot was busy electrocuting a helpless Mega Man when Duo showed up, and had punched Rush into a wall when he tried to stop it.
In Mega Man & Bass, Protoman gets a moment when, after being chopped in half in the opening level, and then getting his own laser shot back at him, takes off the kid's gloves and shoots King with a Hadouken. Eat your heart out, X.
The Hadouken was a translation joke, it's still Badass and awesome, of course.
The real name of his attack is even more so: Big Bang Blast.
8 has the helper robots show up to help you in the two aerial stages. Eddie drops bombs. Beat does a bird missile. Auto, the item maker, shoots a freaking bazooka. And you can have them all on the screen at once, with Rush and Mega himself shooting their own brand of plasma goodness. And one of these is in a Wily Stage, where you even face a boss with this possible setup.
Wily has a CMoA in Mega Man 9 when he talks Light's robots into rebelling. Yes, you read that right, he talks Light's own robots into rebelling against humanity, simply by giving a very valid and true argument about their being arbitrarily destroyed after a set time despite still being very much useful as human servants. It's a shame Capcom didn't follow up on it, because it would've been an awesome twist to the entire Mega Man series.
However, it should be clarified: Wily did not convince them to rampage. He convinced them that they were still useful, and that they should let him repair them so they could continue helping people. Presumably, while he was "repairing" them, he installed their murderous programming. Still, Wily does get major points for even that subtle rebellion, since they are 3-Laws robots, and second law was in effect.
Let's be honest here — Capcom even making Mega Man 9 is a Crowning Moment in and of itself; doubly so for them essentially making a brand new NES game almost a decade-and-a-half after the system was discontinued.
Mega Man himself gets one in 9 upon defeating Wily with the Mad Scientist begging at his feet once again. He then proceeds to use Rush to show him a montage of all the times he's had to beg for mercy in the previous games as a brutal Humiliation Conga. Doubles as a Crowning Moment of Funny.
The introductions of Wily's castles have never been as awesome as the one seen in Mega Man 10. The castle gradually emerges from the darkness as the screen slowly pans it into view. It just makes storming it all the more epic.
DesertMan's scenario. When Sunayama's finished explaining his Evil Plan to Chaud, just as Chaud is about to hand his PET over to the villains... Lan spins around a corner, shouts "MEGAMAN, ATTACK!", and tosses his PET case, MegaMan and all, right at Sunayama's head (as you can imagine, this doubles as a Crowning Moment of Funny). In a series where almost all combat is virtual, this was very refreshing.
In the fourth game, ShadeMan, who's completely immune to MegaMan's attacks, demands that he and Lan return the DarkChip they found. Out of options, MegaMan tosses him the chip... and then shoots it in midair, destroying it. ShadeMan is not pleased. (Fortunately, MegaMan gets a way to damage him in the ensuing battle.)
In the sixth game, MegaMan gets taken over by a giant Internet monster Sealed Evil in a Can, and you have to drag someone else' Navi (Heatman or Aquaman, depending on version) into Internet Hell to defeat him. As much as that could be a Moment, given that you just defeated the main character fused with a massive cybermonster while playing as either a baby with a fishbowl on his head or a manic zippo lighter, that's not the awesome. A few scenes later, MegaMan wakes up from his beating... and the Beast roars back to life. Lan and his dad are panicking. And then your substitute Navi Bright Slaps Rock back into control. Win.
Actually, by that time (when you need to save him from that cult in the Undernet, not when MegaMan first absorbs Gregar/Falzar), I believe you already have the first three crosses(Aqua/Heat + Tengu/Slash + Tomahawk/Elec), so you can use any of those three. Saving MegaMan with Elecman has never felt so epic.
And following the last prelim of the contest, you have access to all Link Navis. So, technically, you can send the Grim Reaper into Hell to go save MegaMan.
The ending in the fourth game. After defeating Duo.EXE, and with only an hour before a computer-controlled asteroid collides with the Earth, MegaMan tries to move the wheel controlling it, but it would not even budge. However, after the whole world starts to cheer for him, Lan goes Full Synchro with MegaMan, and the wheel that wouldn't even budge now spins so hard that it's a surprise that it doesn't fly off its axis. With the music to go along with it, it was perfect.
Let's be honest, Mega Man does something selflessly heroic and suicidally stupid at the drop of a hat to the point where it stops being awesome sometime around game 2. That said, the ending of BN3 felt like they finally figured out how to do a proper Heroic Sacrifice with all the awesome due to such a moment. Even his resurrection after the credits is so well done as a CMOH that finally, FINALLY Mega has some Awesome in his pants. And then they hit us with BN4...
Anyone forget Wily's CMOA at the end of MMBN5? He's an old man who walked into an EXPLODING VOLCANO, just to use a brilliant combination of the Reset Button and a Bright Slap to allow his own son a chance at redemption, and BOTH of them survived!
From MMBN5: Team Colonel, Baryl Bright Slaps Lan/Netto out of a Heroic BSOD and tells him to quit whining and kick ass. He does that, and you get to control COLONEL HIMSELF!
Team Protoman gave us Protoman's exclusive unbridled awesome, and Enzan/Chaud took a punch from Lan and turned it into a Rousing Speech that basically said "take that aggression, and do something positive with it".
MMBN3: The entire scenario where Lan and Mega Man are kicking viral ass to save Mamoru from dying was so Manly Tears inspiring that the whole scenario is a gigantic CMOA for the series in general!
MMBN4: For those who say this game sucked, here's one moment of awesome no one can deny. Lan made some very questionable moral decisions throughtout the game, and Regal's attempts at a What the Hell, Hero? speech at the end were destroyed by the simple fact Lan still gave a damn about humanity, and Regal didn't. The game's story was thin, but it was a barely disguised morality tale that proved that those who ultimately see the good in humanity and are willing to fight for it are the best hope our race has of survival....literally.
Bonus points for being the impetus that gave Lan, Yuichirou, AND Wily the chance to ultimately prove that point by the end of MMBN5.
MMBN6: Joe Mach's awesome Heel-Face Turn, courtesy of beating the piss out of his former World 3 allies because his conscience couldn't stand the thought of those assholes hurting a child.
Back to BN5, there's the Brain Navi of both games beating the living shit out of the impostors of himself and MegaMan. Cool when SearchMan does it in ProtoMan, but more awesome in Colonel, considering the fact that your Brain here is NumberMan.
The very end of the series. MegaMan has been taken over by the Cybeast. Lan can't do anything to save him. The Megabeast then warps over to Iris and Colonel, weak from fighting the opposite Cybeast. The two unite to form the original Colonel with the emotion that became Iris. Colonel then rushes at the Megabeast, tears the Cybeast soul out of his body in a single strike and then performs a Heroic Sacrifice to destroy it once and for all.
Juno as a final boss has a moment. His defenses are staggeringly high, especially compared to all the other bosses in the game. He doesn't have very much health, maybe both forms' gauges combined to equal Bruno's, but he takes so little damage and hits so hard that one missed step means getting smacked in the face with an attack that takes anywhere from a quarter of your health to crushing your Shield and leaving you with no health.
Speaking of Juno, he crosses the Moral Event Horizon of the Bonnes, so they decided to free Mega Man from Juno's trap and send him off to stop Juno from destroying the island.
Another Bonne one, in the first game they seem to die after their airship is destroyed. In a secret side passage in the final dungeon though, you find them holed up with yet another new robot. It then powers up, destroying the building it was contained it, and proceeds to attack with every weapon the previous robots have had!
Data, the monkey-like robot who up until then did not much more than save your game, stopping Eden from destroying the island simply by telling the computer Juno was malfunctioning and his orders were invalid.
It's hard to overstate just how big a twist it is (for both the player and Mega Man, who spends most of the scene with his jaw hanging open) when the character who, up until that point, had just been the squeaky, cute little Non-Human Sidekick/save-point suddenly turns around and pulls a one-man Big Damn Heroes moment using nothing but his own administrative authority...
Data: Interrupt command. Priority command rerouted to Purifier First Class Mega Man Trigger. Under suspicion of malfunction, Bureaucratic Model Third Class Juno has been deactivated by Mega Man Trigger as per Ordinance 103. Mega Man Trigger hereby requests the indefinite postponement of the previous Reinitialization order, and the deletion of Bureaucratic Model Juno's back-up data. Trigger hereby assumes all Bureaucratic authority for the District, and will petition Mother for guidance at a future date.
Computer: Command reroute acknowledged.
"Tron, get on board! It's time to activate...Bruno!"
The battle with the Bonnes' airship: Mega Man single-handedly shoots down an airship the size of a city.
After Legends 3 was canceled, thousands of fans are calling for Capcom to reconsider. Even if they don't, the fans' voices were heard.
Forget "thousands of fans". Basically the whole fanbase is putting up a fight for this. All the more awesome when you understand that the Mega Man fanbase is one of the most Broken Bases in video game history.
The third game has one at the end. After beating the Big Bad, it comes back as powerful as ever. After a quick motivational speech from a thought-deceased comrade, Geo takes full control of The Corruption and transforms into his ultimate form. Though this is fairly par for the course, the CMOA happens after he transforms - he stands there for about five seconds, then glances over his shoulder at the Big Bad. Nothing more. Cue unloseable boss fight.
Another one for the villains in Star Force 3: The first few scenarios are pretty light-hearted and more or less typical early game fare, until you beat Club Strong and Joker appears for the first time. There's barely time to react before he utterly dominates the heroes, nearly kills Luna and whiplashes the plot so hard it's a miracle it doesn't just break in two.
What fails to be remembered a lot is how Joker has been forced to detonate against his will. He's having the psychotic breakdown of a lifetime, and then Ace steps up to bat. Joker actually starts encouraging him as he laughs.
In Star Force 2 there is another one, where Geo has just been defeated by Rogue and looks like he's about to be destroyed and the OOpart taken, then in a flash of light hits and who comes to save him in Big Damn Heroes fashion... Harp Note. This is after she supposedly joined the bad guys.
Geo's Return near the end of the first game, when he comes after the Jamming messing with his Protectorate.
Bud gets a small one immediately after this when he humbly asks to become Geo's brother.
Taking on each of the ten straight virus battles in the games, especially the one in the first game, where the final fight is against a trio of Jammer3Gs.
Star Force 3 basically took the plot from the final chapter of Battle Network 4 and extrapolated it into an Evil Plan worth acknowledging. Some respect for the writers is due.
Heartless wrenching control of Meteor G away from King. As she does so she points out how utterly misled he was; not one of his subjects ever granted him any value as leader — even Joker was in his employ only so he could do what he felt like.
King wrenching it back by becoming an EM Being. And then fusing with the Crimson Dragon.
An impressive number crop up in the Season Finale of the Tribe anime.
Burai, near death, showing up basically to reaffirm that he wants Orihime and her crew to GTFO. He ends up in a fight with Hollow, which has them both frequency-jumping and fighting at the same time.
Goyouda, totally out of his Super Weight, as always, climbing down to try and retrieve the Sword of Berserk from its pedestal.
I don't care if it's Ra Mu or ramen... Goyouda will never let it be revived!
Harp Note saving him from being suffocated by Phantom Black... and then Cancer Bubble saving her by Tidal Waving Phantom Black and Yeti Blizzard before they've had the opportunity to do much more than look threatening. And then he and Harp Note bicker about his sense of priorities.
Harp Note: What's more important? Sorting receipts or the fate of the earth?!
Cancer Bubble: But I'm an FM-ian...
Harp Note: No buts! You'd die too, if this world disappears!
YB and PB are both washed away. Orihime just summons a barrier out of nowhere, totally unflappable.
Subaru has to run what is effectively several miles of stairway to get to the throne room, and then he dives headlong into the the lake at Ra Mu's base to rescue War Rock.
Goyouda taking a pot shot at Hollow. It doesn't do anything worse than get his attention, but that's enough.
Tribe King Rockman taking everything Hollow has without doing so much as adjusting his balance, and then dispersing Hollow's Lightning Bazooka with a wave of his sword.
Luna, Gonta, and Kizamaro back on Earth are surrounded by viruses and still fighting. Luna gets some small Character Development, too.
Tribe King Rockman cleaves Hollow in two. And Orihime's magnificent, totally unexplained Freak Out.
The whole episode deserves a Brilliant Animation Gold Star.
A couple show up elsewhere in the anime, as well.
The Satellite Admin'sHeroic Sacrifice against Andromeda. They manage to destroy both arms and leave it just weak enough for Subaru to finish it off with the Break Sabre.
Tsukasa shows us he knows how to go Jumping Off the Slippery Slope by murdering Gemini to fill up the last bit of the Andromeda Key. And still in Super form, he makes off with the Andromeda Key, Laughing Madly the whole time. He also demonstrates he's not stupid enough to pick a fight, instead sending Rockman racing back down to the planet to catch the Andromeda Key after he ditches it. As Andromeda is about to destroy it. Rockman just barely catches it.
And then he has the biggest Oh Crap in the series when he sees the green light catching up to him. This is totally justified, since, when it does hit him, it rips him apart.
Rockman totally wiping the floor with all of the FM-ians when he first gains the Star Force.
Cygnus Wing returning, and proving he's not here to mess around. He unites all the FM-ians save Gemini under his own leadership and actually gets his hands on the Andromeda Key for a few glorious moments.
He was pretty damn good in his first appearance, too. Most FM-ians would cause some mild chaos when they showed up. Cygnus Wing's plan was to hit AMAKEN with a satellite!
Lyra Note's debut as Mega Man's partner has her playing some rock and roll (the Theme Song in Japan). While she doesn't do much more than convince Gemini Spark it's not worth their time to deal with her, too, she basically managed to save Geo's life by giving herself a theme song.
Also part of Gemini Spark's debut, Geo deciding to run off and fight Gemini with or without Mega's help.
On that note, Gemini Spark's debut, for Gemini. He basically spends fifteen minutes making it clear that Rockman is completely outclassed against him. Even when Geo starts using his brain and manages to split the two Sparks apart, he still loses against Black. Even Mega admitted at the end that this was their complete defeat.
Goyouda, who hangs out near the bottom of the series' Super Weight, regularly entering battle with superhuman foes, including the viruses, the virus-man, the FM-ians, and the UMAs, not to mention Andromeda. He insists his subordinates show the same dedication.
Don't be an idiot! The patrol light on my head called us here to defeat this evil!
Crown Thunder gets a little bit Crazy Awesome in his debut; he surfs around on a set of Roller Coaster cars as he fights.
It reached third place in the iTunes store days after its release. More significantly, it's #63 and climbing in iTunes' Top Grossing Apps. Of the 1,136 ratings, 889 of them are five star reviews; while most of those are referral codes, it shows a lot of people have the game and care enough to rate it.
Hell, his entire apperance is a Crowning Moment Of Awesome. He was one of the few characters who never got portraited as weak, dumb or incompetent.
Of all people, Dr. Wily got one in "The Mega Man in the Moon". When a human girl, Tina, stowed away on the rocket ship to see her father, Wily promptly held her hostage. When Mega came to save her, Wily physically grabbed Tina and told Mega to take a hike or else he'd activate her jetpack. Sending her into space. Mega promptly left and Wily was free to continue his plan.
Roll got one in "Terror of the Seven Seas" when she successfully infiltrated Wily's base, defeated Cut Man, avoided Elec Man and Bomb Man, and got out safely. Given her track record in season one you might be waiting for her to get caught, but it doesn't happen, establishing her as a proper action girl.
Near the end of "Mega-Pinocchio", Mega Man pretended to be evil to get close enough to steal Magnet Man's power. How did he accomplish this? With a high-five.
Protoman got one in "Bro Bots". When Mega Man found out that he was only pretending to be good, he was understandably angry. However, Mega couldn't act to stop him and Wily because of a 'scrambler chip' Proto had planted on him earlier. Protoman offered to remove it if his brother would join him. When Mega refused...
Proto Man: Whatever you say, bro. *shoots Mega Man, sending him flying into the wall*
Protoman got another one in "Showdown at Red Gulch". Wily had his robots powered up with meteorite fragments, and Proto warned Mega that he was out of his league. Mega Man ignored his warning and tried to get him anyway. Protoman's response?
"I hate to say I told you so, but..." *shoots him* "I told you so!"
Eddie got one in "Mega-Pinocchio". When Mega Man jumped in front of Protoman's shot to protect the statue of Abraham Lincoln, he was unable to move. Protoman went to finish him off...and Eddie charged up the stairs, knocked Protoman over, and gave Mega Man an Energy Tank Can to power him back up.
The mayor of the city got one in "The Big Shake". Dr. Wily invented an earthquake machine that, well, created earthquakes. After an attack on Light's lab, Wily believed he'd killed them all. Wily then threatened the mayor, telling him Mega and Light were out of commission permanently, to submit, and to be quick about it as he had other cities and countries to deal with. The mayor refused and told him to shake the city to the ground. They wouldn't surrender. He'd rule nothing.
"Master of Disaster" was one of the...stranger episodes, but it had an awesome moment from Protoman. When Wily found a genie and ordered him to destroy Mega Man, he ignored the robots. After the genie tried and failed several times, Protoman told him to stuff it and let the robots give it a shot.
Granted, the 'bots failed, too, but he talked back to a genie.
In "Ice Age", Iceman defeated Mega Man, Roll, and Rush about 3 times in the span of a single episode. And he kicked Rush while he was frozen, breaking him into pieces.
Metalman got one in "Future Shock". After pinning Mega Man under a pipe, he tried to saw his head off. Hardcore!
"Mega X" was one for just about everyone involved, animators included, but special mention goes to Dr. Wily, who saved Vile and Spark Mandrill from X.
On the heroes' side of things, it had been shown that none of the present-day tech could affect Vile and Spark Mandrill; Mega Man experienced this firsthand. But it didn't stop him from standing in front of the time portal to stall them until X could get at them. When Vile retaliated, Mega and Rush pulled X out of the way of his shot.
X was attacked by Cutman's Rolling Cutter. He caught the blade.
Roll got another in "Bot Transfer" when she beat up Snakeman (technically it was Mega Man in his body, but still) with a lamp.
Rush got one in "The Strange Island of Dr. Wily," where he was instrumental in helping Mega fight the giant Stone Bot, even distracting him when Mega was briefly captured. As bonus points for those who didn't much like Rush, he stayed relatively silent during the fight.
Dr. Light got one in "The Mega Man in the Moon" when he interrupted Wily by cutting into his transmission screen; generally Wily did that to the good guys.
Light got another in "Cold Steel" when, after being freed of brainwashing, said this in response to Wily's tirade.
Wily: Why!? Why am I surrounded by fools?
Light: Maybe because that's all you know how to build, Dr. Wily.
Protoman got one in "Campus Commandos," as he donned a jetpack and silly-looking goggles to see Mega when he was in stealth mode. The resulting aerial fight had Proto doing a midair somersault while vaulting down the side of a building, shooting at Megaman mid roll.
Any time Rush goes into jet mode by himself to save Megaman.
Mega Man is about to finish off Wily in Issue 4, but he runs out of ammo. Wily takes advantage of the situation to fly away. Rather than let Wily escape, Mega Man runs towards a piece of metal left behind by the fight, jumps off of it, and proceeds to blast Wily's machine at point blank with a charged shot, keeping Wily from escaping. Also, this is the very first time Mega Man has ever fought Wily. Can't wait for the Wily fight in the Mega Man 2 arc!
Wily's buried under the remains of his Wilymachine, complaining that Dr. Light's robot had beaten him, but "at least I'll die with the satisfaction of knowing I was the better man." Cue Rock digging Wily out to save his life.
In Ultimate Marvel vs Capcom 3, the 'Days of Future Past' stage features a poster of several missing characters from the previous Marvel vs Capcom games. All characters appearing on the mugshot poster are tagged with either 'Apprehended' or 'Slain'... Save Megaman. Overlaps with Fridge Brilliance when one realises that in a bad future where Sentinels have gone on a Terminator-esque rampage against Mankind, only Megaman would continue to fight on, for Everlasting Peace.
Even better, Version 2 was released, which fixed complaints fans had and added a bonus character.
Mega Man is in Super Smash Bros. 4 with a slew of Robot Master weapons. His Final Smash summons other Mega Man incarnations to fire a huge beam of energy, a la Pokémon Trainer's Final Smash from Brawl.