[[quoteright:350:http://static.tvtropes.org/pmwiki/pub/images/mm4.png]]
The fourth game in the ''VideoGame/MegaManClassic'' series for the NES. It was released in Japan in December of 1991, closely followed by a North American release in January of 1992. PAL territories didn't get it until nearly a year later, in December of 1992. It has since seen numerous rereleases, including the ''Rockman Complete Works'', ''Mega Man Anniversary Collection'', UsefulNotes/VirtualConsole, UsefulNotes/PlayStationNetwork and ''Mega Man Legacy Collection''.

It had been about a year since the events of ''VideoGame/MegaMan3''. Dr. Wily has disappeared after the final battle, having been apparently crushed by the falling debris from his Wily Castle, and the world is at peace. But this period is short-lived (isn't it always?) when Dr. Light is contacted by a new MadScientist named Dr. Cossack. Tired of Dr. Light receiving all of the recognition for his accomplishments while his have been ignored, Cossack intends to prove to the whole world that he is the superior roboticist by [[TakeOverTheWorld sending his own breed of Robot Masters out to conquer it]]. Already, eight cities have fallen behind his iron curtain, but Mega Man isn't one to stand by and let this happen, so he sets out to liberate the fallen cities from Cossack's robots.

However, once Mega Man defeats all eight Robot Masters and confronts the doctor himself in his citadel, it's revealed that Dr. Wily is still alive, and had kidnapped Dr. Cossack's daughter, Kalinka; blackmailing him into use his robots to battle his nemesis and further his own plans. Mega Man defeats Wily, who escapes, and peace is restored once more.

Robot Masters:
* DWN-025: Bright Man, weak to the Rain Flush, gives the [[LightEmUp Flash Stopper]]
* DWN-026: Toad Man, weak to the Drill Bomb, gives the [[HostileWeather Rain Flush]]
* DWN-027: Drill Man, weak to the Dive Missile, gives the [[ThisIsADrill Drill Bomb]]
* DWN-028: Pharaoh Man, weak to the Flash Stopper, gives the [[ThePowerOfTheSun Pharaoh Shot]]
* DWN-029: Ring Man, weak to the Pharaoh Shot, gives the [[RingsOfDeath Ring Boomerang]]
* DWN-030: Dust Man, weak to the Ring Boomerang, gives the [[ExtraOreDinary Dust Crusher]]
* DWN-031: Dive Man, weak to the Skull Barrier, gives the [[HomingProjectile Dive Missile]]
* DWN-032: Skull Man, weak to the Dust Crusher, gives the [[CastingAShadow Skull Barrier]]

See also ''VideoGame/Rockman4MinusInfinity'', a [[GameMod ROM hack]] that plays like a love letter to the ''VideoGame/MegaManClassic'' series and Creator/{{Nintendo}} as a whole ([[VideoGame/{{Kirby}} some games]] [[VideoGame/{{Gradius}} in]] [[VideoGame/TheLegendaryStarfy particular]]).

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!!Tropes:

* AIBreaker:
** Toad Man has an [[AlwaysAccurateAttack Always Accurate Rain Flush]] activated by a RainDance. Naturally, the only way to make this fair is to let players interrupt the dance somehow. The developers, however, DidntThinkThisThrough - what did they decide upon? Shooting him. No special tricks, just shooting him with a weapon that hurts him. His only other trick is to try and jump on the player, which is both pathetically easy to dodge (don't stand still) and only activates under a specific circumstance (if Toad Man is attacked during his MercyInvincibility). He's the [[ComplacentGamingSyndrome Player Preference]] for "first Robot Master kill" for a reason. Shoot, move right, shoot, move left. Only the bosses of ''VideoGame/CastlevaniaIISimonsQuest'' are easier.
** The Cossack Catcher will completely stop and reset its pattern whenever Mega Man ''slides'', leaving it open for attack while it does nothing at all for a period (maybe Dr. Cossack's just ''that'' impressed by it?).
* AllThereInTheManual:
** While this game does avert this in regards to both its story and that of the overall series, you wouldn't know that you were fighting in different cities to free them from Dr. Cossack's robots. Even worse, you wouldn't know Cossack was (seemingly) after world conquest at all unless you read the Japanese manual; the Western intro and manuals imply he's more interested in destroying Mega Man than world domination.
** Why are this game's Robot Masters listed as Wily Numbers despite being made by Dr. Cossack? A short-lived Japanese magazine has the answer.[[labelnote:*]]While Cossack did create the Robot Masters, Dr. Wily heavily remodeled them to fight Mega Man.[[/labelnote]]
* AlwaysAccurateAttack: The Rain Flush, which acts like a SmartBomb. Best of all, it [[UnblockableAttack ignores all defenses that aren't an outright immunity]], including '''''Metall hats'''''.
* AmericanKirbyIsHardcore: Compare the [[http://image.gamespotcdn.net/gamespot/images/box/4/4/4/563444_29033_front.jpg US Boxart]] with the [[http://image.gamespotcdn.net/gamespot/images/box/4/4/4/563444_59407_front.jpg European one]]. Though unlike other instances of the trope, the Japanese art (pictured above) is just as, if not more, dynamic and hardcore than the Western art.
* AreaOfEffect: The [[HavingABlast Drill Bomb's]] explosion hits a larger area than the drill itself. Comes into effect against the second Wily Machine, which is weak against the explosion, but will completely deflect all strikes with the drill itself, making for some tricky timing.
* AutoScrollingLevel: The third Cossack stage is one of these, a rarity in the series.
* {{Balloonacy}}: The Balloon item plays with this trope, making FloatingPlatforms out of large, red balloons.
* BarrierWarrior: Skull Man. You too, once you receive his Skull Barrier.
* BehindTheBlack: After the first part of Pharaoh Man's stage, you have to drop down a crevice to continue, but jumping over it and going forward is how to get the Balloon Adaptor.
* BigBad: Dr. Cossack. [[spoiler:Until we learn that he was a pawn in [[TheManBehindTheMan Dr. Wily]]'s plans.]]
* BlackoutBasement: Parts of Bright Man's level become this if you shoot the 100 Watton enemies that fly through the area. Shoot a Dompan to turn the lights back on.
** The final fight against the Wily Capsule takes place in a dark, underground laboratory - a ''literal'' Blackout Basement!
* BlindedByTheLight: Although it ''appears'' {{time stands still}} when the Flash Stopper is used, in reality what it does is flash an intense light that blinds and stuns enemies for a short time.
* BookcasePassage: How Mummiras appear; part of the wall will flip around to reveal them. Destroying them destroys said passage too, by the way.
* BossArenaUrgency: Mothraya destroys part of the floor with one of its attacks.
* BubblyClouds: Subverted somewhat with Ring Man's stage, which begins in a cloudy tower but then goes into space and is filled with hippos and small floating Saturn-esque enemies. Played straight with the third Cossack stage, which takes place in the sky above the citadel and where platforms are often obscured by clouds.
* BuildLikeAnEgyptian: Were you expecting Pharaoh Man's stage to be anything else?
* ChargedAttack: This is the first game that allows Mega Man to charge up his Mega Buster. The Pharaoh Shot is this too.
* CheckpointStarvation: An annoying one in Cossack Citadel 1 - dying against Mothraya will send Mega Man back to the midpoint of the level, ''not'' in the boss corridor.
* CollisionDamage: A ''Mega Man'' staple of course, but in this game you need to be extra careful. Enemies (especially bosses) dish out a ton of it, more than most games in the series. The Robot Masters seem to have grown savvy and become very fond of getting up in your face, as most of them actually use this as an attack strategy rather than using their own weapons.
* TheCommiesMadeMeDoIt: Ironically, in this case it's the ''Commie'' who was made to do it[[labelnote:*]]Though Cossack has never been stated to be communist, but let's not ruin the joke[[/labelnote]] - Dr. Cossack was blackmailed by Wily into conquering the world and destroying Mega Man with his robots.
* CraniumRide: Bright Man's stage has you ride robotic grasshoppers (Battans) over spikes on a few occasions. Pharaoh Man has a similar gimmick in his level with Hovers.
* DamselInDistress: Kalinka Cossack, who's being held hostage by... [[HijackedByGanon Dr. Wily]]. However, Mega Man doesn't rescue her; Proto Man does.
* DemBones: Skull Man and his stage appropriately have a bone motif. [[SkeleBot9000 Skeleton Joes]] are a recurring enemy in this level, and they also appear in the first section of Cossack Citadel.
** Wily Machine 4 also acts as the first Wily Machine in the series to use a skull motif.
* DenialOfDiagonalAttack: Averted by the Pharaoh Shot, which can be aimed diagonally; played straight with everything else.
* DiscOneFinalBoss: [[KidnappedScientist Dr. Cossack]]. A special note is that this is the first classic Mega Man game to [[HijackedByGanon pull this trick]] (and certainly not the last!).
* DiscOneFinalDungeon: [[GloriousMotherRussia Dr. Cossack's Citadel]].
* DownInTheDumps: Dust Man's stage is a scrapyard with a large compactor and incinerators close to his lair.
* DownTheDrain: Most of Toad Man's stage and part of the first Wily Castle level.
* DramaticThunder: Cossack's Siberian Citadel is introduced this way.
* DualBoss: The Cockroach Twins from Cossack Citadel 3.
* DummiedOut: Pharaoh Man's level was originally supposed to include a [[Art/TheSphinx Sphinx]] MiniBoss on the path to the [[{{Balloonacy}} Balloon Item]]. This boss did not make it to the final release, and the only data left of the Sphinx was the snake on his forehead, its chin, and some sort of sphere that Mega Man would have stood on during the battle.
** Unused sprites of Cossack and Wily pointing and talking are present; presumably, these would've been used in the post-Cossack Catcher cutscene.
* EverythingMakesAMushroom: Dr. Wily's castle makes a skull-shaped mushroom cloud when it goes up at the end.
* FastTunnelling: Drill Man tunnels underground quickly using his [[ThisIsADrill many drills]].
* FloatingPlatforms: The Balloon item found in Pharaoh Man's stage makes these.
* {{Foreshadowing}}: Wily is only made aware of Proto Man's betrayal at the end of this game, which would lead to the plot of [[VideoGame/MegaMan5 the next installment]], where Wily frames Proto Man, possibly as revenge.
* GameBreakingBug: [[http://www.youtube.com/watch?v=-cXOfi2Y8PA It is possible to]] ''kill'' Dr. Wily as he's ejecting from his exploding Wily Machine if you fire the Rain Flush and time it just right, so the rain starts as he's flying out. However, doing this will mess up an EventFlag that ends the level, meaning you're stuck in that room, forcing you to reset. Though obviously unintentional, given how you essentially break the "never harm humans" rule of being a robot, [[FridgeBrilliance this makes sense]].[[labelnote:*]]But hey, at least [[ForWantOfANail you change the timeline]] so that Wily's future plots, the [[VideoGame/MegaManX Maverick Virus]], and the [[VideoGame/MegaManZero Elf Wars]] never happen, right?[[/labelnote]]
* GloriousMotherRussia: The Cossacks; {{Fanon}} has taken it UpToEleven.
* GrapplingHookPistol: The Wire, found in Dive Man's stage.
* HijackedByGanon: The first time (of many) where Dr. Wily enacts this as part of his current world conquest scheme.
* HomingProjectile: The Dive Missile. Many enemies like Mobys and Kabatoncues also use this against Mega Man.
* HoppingMachine: Toad Man. Most of the Robot Masters jump, but Toad Man's only mode of movement is to [[CaptainObvious hop around like a toad]].
** The Jumbig enemies "attack" by hopping towards Mega Man.
* HostileWeather: The Rain Flush makes acid rain to damage all foes on screen. Said rain was initially beneficial, until Dr. Wily modified Toad Man to make it acidic.
* HyperDestructiveBouncingBall: What the Super Ball Machine Jr. enemies fire; it's particularly destructive as it fires its giant bouncing balls through the narrow corridors of Skull Man's stage.
* IHaveYourWife: Well, daughter. Either way, this is how Wily gets Cossack to step in line until Proto Man frees her.
* InvulnerableAttack: Drill Man is invulnerable while drilling into the ground, Dust Man is invulnerable while using his VacuumMouth.
* JustInTime: Just as Mega Man is just about to finish off [[DiscOneFinalBoss Dr. Cossack]] (or more accurately, the Cossack Catcher he uses), unaware that Cossack is actually being forced to fight against his will, Proto Man teleports in with Dr. Cossack's kidnapped daughter, Kalinka, [[HijackedByGanon exposing Dr. Wily as the mastermind behind everything]].
* KidnappedScientist: Though more on an emotional level, Dr. Cossack is forced to attack the world by [[HijackedByGanon Dr. Wily]].
* KingMook: The boss of Wily Castle 1 is Metall Daddy - a giant Metall that creates/summons smaller Metalls.
* LedgeBats: This game introduces Up 'n Downs, an annoying little enemy that hides in BottomlessPits and jumps out just as you're jumping over them, and can easily knock you in if you're not expecting them. Nearly every game after this has a variation of these guys.
* LosingYourHead: Mummira, the mummy robots from Pharaoh Man's stage (and Wily Castle 2), attack by using their mummy bandages to throw their heads at Mega Man.
* LuckilyMyShieldWillProtectMe: The Skull Barrier.
* TheManBehindTheMan: Dr. Wily is the real BigBad of the game.
* MultiMookMelee: Wily Stage 1, which is full of Metalls and all their variations followed by the [[KingMook Metall Daddy]] boss.
* NephariousPharaoh: Pharaoh Man is one of the Robot Masters fought in this game. He's not an actual pharaoh, though he was originally built to explore pyramids. His stage begins as a ShiftingSandLand and progresses into a TempleOfDoom.
* NoobBridge: The Drill Bomb's remote detonation property (one of the reasons its one of the better "explosive" weapons in the series) is often overlooked (push B again before it hits its target). The second form of Wily Machine 4 is basically a test to see if you know about it.
* NotSoHarmlessVillain: Sure, Toad Man may look goofy, have broken A.I. and be unable to use his weapon against skilled players,but ''if'' he manages to get his Rain Flush off, prepare to get hit with a powerful, unavoidable barrage of acid rain. In-universe, he could very well be the most dangerous of Cossack's Robot Masters by virtue of this attribute alone.
* OffscreenStartBonus: In the first stage of Dr. Cossack's Citadel, there's a hidden E-Tank buried in the snow to the left of your starting point.
* OneWheeledWonder: Mono Roaders.
* ThePowerOfTheSun: This is what the Pharaoh Shot acts as - with the weapon using charged solar energy and even resembling a small sun when charged up.
* PrecisionGuidedBoomerang: The Ring Boomerang - it's even in the name.
* PullingThemselvesTogether: Don't shoot a Skeleton Joe with a charged Mega Buster or Pharaoh Shot attack, and it'll do this after a short while.
* QuicksandSucks: The first part of Pharaoh Man's level involves this.
* RainDance: How Toad Man summons his acidic [[HostileWeather Rain Flush]], but it's also his AchillesHeel - if he's shot/interrupted before his dance is complete, [[AIBreaker he'll stop and completely negate his Rain Flush]].
* ReluctantMadScientist: Dr. Cossack really doesn't want to conquer the planet or fight Mega Man, but Wily's got his daughter as a leash.
* RenegadeRussian: Although Dr. Cossack conquers eight cities and threatens the world, it's subverted in that actually a pretty decent guy, and Dr. Wily was the one behind the plot.
* RevivingEnemy: The [[SkeleBot9000 Skeleton Joes]] in Skull Man's stage. Only a charged Mega Buster or Pharaoh Shot can destroy them (or by shooting them with the Flash Stopper active).
* RingsOfDeath: The Ring Boomerang.
* ScaryScorpions: Sasoreenus are scorpion robots found just outside of Pharaoh Man's TempleOfDoom, emerging suddenly out of the [[QuicksandSucks quicksand]] to attack.
* SeaMine: Located in [[UnderwaterBase Dive Man's stage]].
* SharedLifeMeter: The game has the Cockroach Twins, two robots fought one after the other.
* ShoutOut: Film/{{Mothra}}ya, the first boss of Dr. Cossack's Citadel.
** [[SkeleBot9000 Skeleton Joes]] are quite similar to the [[NightOfTheLivingMooks Stalfos]] from Franchise/TheLegendOfZelda series.
** The whale miniboss in Dive Man's stage is named [[Literature/MobyDick Moby]].
* SkeleBot9000: The Skeleton Joes that inhabit Skull Man's stage are this. They even [[PullingThemselvesTogether reassemble]] if they're not totally destroyed by a ChargedAttack. And Skull Man himself, of course.
* SkullForAHead: Skull Man, obviously (though it's more of a skull-shaped helmet). The Skeleton Joes he uses as minions also count.
* SmartBomb: The Rain Flush is the first weapon in the series to act as a means of destroying all enemies onscreen, and it's damn good at it, since not only is it [[AlwaysAccurateAttack completely unavoidable]], [[UnblockableAttack all shields, even Metall helmets, are ignored by it]].
* SpoiledByTheManual: Sort of - the Japanese manual uses "No. XXX" when listing the Robot Masters, but officially, the Robot Masters in this game are part of the DWN series. [[SarcasmMode Whatever could that indicate about Wily's involvement in this game?]][[note]]Though ''Manga/MegaManMegamix'' does get around this by listing them as part of the non-existent DCN series.[[/note]]
* SpreadShot: The Dust Crusher is of the Exploding Shot variant.
* SuperHeroOrigin: Mega Man's origin story had previously been AllThereInTheManual, but this game goes ahead and puts this in the game's intro.
* TeleportSpam: This is the first game where you fight Wily in the Wily Capsule, and it uses this tactic. Of course, since it's [[BlackoutBasement completely dark]], he could just be flying from one place to the next in the darkness.
* TempleOfDoom: Under the sandy desert, this is what Pharaoh Man's stage becomes.
* TimeStandsStill: Although this is ''not'' how the Flash Stopper works (see BlindedByTheLight), it does give off this effect to a lesser extent, since most foes (and even a few missiles and projectiles) will freeze in place when it's used.
* ThisIsADrill: Drill Man, and by extension the Drill Bomb.
* TrappedInVillainy: Dr. Cossack. Sure, he's not threatened to death, but what about his daughter?
* UnblockableAttack: The Rain Flush hits all enemies on the screen, including shielded ones like Metalls hiding under their hats. This also applies to Toad Man when he uses it, so preventing him from using it is your only hope of avoiding it.
* UnderwaterBase: This is where Dive Man sets up shop.
* UtilityWeapon: The Drill Bomb is the only weapon that can destroy hard walls in Dr. Cossack's Citadel.
** The [[GrapplingHookPistol Wire]] can damage foes, but it only does one bit of damage per hit, making it generally useless compared to other weapons for fighting.
* VacuumMouth: Dust Man will attempt to suck in trash ([[CollisionDamage and Mega Man]]) using the duct on top of his head.
* WarmUpBoss: Toad Man is the easiest boss this time around. [[AIBreaker He can't even attack you as long as you keep shooting him]].
* YouDirtyRat: The Rattons in Toad Man's [[DownTheDrain sewer stage]].
* ZeroEffortBoss: Using the Flash Stopper on Pharaoh Man turns him into this - he can't move or attack while it's in effect, you can pump him full of solar bullets, and in doing so activate the Flash Stopper again when its effects wear off. The only challenge is in how fast you can mash the shoot button until he's dead.
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