Dr. Wily's latest scheme has seen him hijack a supercomputer that governs daily life across the world, causing abnormal weather, transportation failures, and other such chaos. If that weren't enough, he also sends out an army of robots to cause chaos and mayhem, and as per usual Mega Man sets out to stop him. In his way are eight rebuilt Robot Masters, along with Wily's second attempt at creating a Mega Man Killer, Punk.
Mega Man III combines the expanded campaign from Mega Man II with the polish, execution and difficulty of Dr. Wily's Revenge, and as such is generally regarded as a better game than both of its two predecessors, albeit not quite up to the standards of the two following entries. The gameplay is pretty much identical to the NES Mega Man 4, meaning that the Charge Shot is added to Mega Man's repertoire for this outing.
Robot Masters from Mega Man 3:
- DWN-019: Gemini Man, gives the Gemini Laser
- DWN-022: Snake Man, gives the Search Snake
- DWN-023: Spark Man, gives the Spark Shock
- DWN-024: Shadow Man, gives the Shadow Blade
Robot Masters from Mega Man 4:
- DWN-027: Drill Man, gives the Drill Bomb
- DWN-030: Dust Man, gives the Dust Crusher
- DWN-031: Dive Man, gives the Dive Missile
- DWN-032: Skull Man, gives the Skull Barrier
The remaining Robot Masters from 4 NES were held over until the following Game Boy outing.
New for this game:
- MKN-002: Punk, gives the Screw Crusher
- 11th-Hour Superpower: The Screw Crusher is this game's unique weapon, and it boasts high ammunition, effective on a number of enemies, and is the only weapon that can damage the Final Boss. Like the past two games, though, you're only given the chance to use it in the final stage, and it isn't saved with passwords (though by getting a Game Over and returning to the stage select, it can be brought into the second set of Robot Master stages).
- Ability Required to Proceed: Most of the second set of Robot Master stages require the use of the Rush Coil or Rush Jet to proceed. Notably, Dust Man's stage requires using Rush Coil over a long bed of spikes — and using Rush Jet to fly over it isn't an option because defeating Dust Man is the only way to get it.
- All There in the Manual: None of the storyline is explained in the game, which seamlessly hides the fact that the Western storyline is completely different (with Wily instead trying to harness the energy of Earth's core via his Wily Station, wih no mention of the supercomputer subplot).
- Anti-Frustration Features: The Wily Station has a second checkpoint in the section right before the final boss, allowing the player to recharge the Screw Crusher if (for whatever reason) they run out of it during the second phase.
- Astral Finale: Averted. This is the only game in the Game Boy series in which Mega Man doesn't go to space at any point.
- Balance Buff: Several of the more underwhelming weapons from Mega Man 3 and 4 were given a power boost in this game to make them more worthwhile.
- The Gemini Laser deals more damage, pierces through enemies, and moves faster.
- The Search Snake isn't as notable, but it can harm certain types of enemies immune to Mega Man'a other weapons.
- The Spark Shock lets you pause and switch weapons to take out a paralyzed enemy, making it infinitely more useful.
- The Skull Barrier can take three hits from projectiles before dissipating.
- Blackout Basement: The Hologran enemies present in Shadow Man's stage and Wily Station cause the entire screen to go dark whenever they appear. This time, however, their black starfield effect also covers up the HUD.
- Clipped-Wing Angel: The final form of the Wily Machine has only one easily-dodged attack that deals a pittance of damage, especially compared to the first form. It also remains stationary, again contrasting its first form. On the flip side, only one weapon can harm it and the challenge comes from trying to hit him with it, but even then a player's not likely to run out of ammo.
- Contractual Boss Immunity: Like Enker before him, Punk is only vulnerable to the Mega Buster; all other weapons are useless on him. This also applies to the Wily Machine, which is only damaged by charged Mega Buster shots in its first form, and the Screw Crusher in its second.
- Crutch Character: The Shadow Blade is downgraded to this. It kills most enemies in the first four stages in 1-2 hits, but is far less effective on the enemies from Mega Man 4.
- Deadly Disc: Punk's Screw Crusher, which is thrown in an arc and has a high ammunition level. Considering it's the only weapon that can beat the Final Boss's second form, you'll need it.
- Dem Bones: Skull Man, his stage, and the Skeleton Joe enemies.
- Dramatic Thunder: Present when Mega Man arrives outside the newest Wily Castle following the defeat of the first four Robot Masters.
- Everything Makes a Mushroom: In the ending, Dr. Wily's smoking UFO drops into the sea with one of these, albeit shaped like a skull. Which then makes a Single Tear.
- Hard Levels, Easy Bosses: Despite the game's notoriously difficult level designs, its Robot Master battles are actually pretty easy for the most part, thanks to the introduction of the Mega Buster's charge ability.
- Homing Projectile: The Dive Missile returns from Mega Man 4, and is a little more useful thanks to the Game Boy's smaller screen size.
- Jungle Japes: Snake Man's stage is set against a jungle background, unlike his original NES stage. However, not much is done with it, outside of giving the original "the ground is made of giant robot snakes" motif a more natural setting.
- King Mook: Although the regular kind are absent, Giant Suzy acts as a giant version of the Adhering Suzy (or Octopus Battery) enemy from the first game (and Dr. Wily's Revenge).
- Long Song, Short Scene: Punk's leitmotif ends abruptly when Mega Man enters the room they fight in, before it can loop.
- Marathon Level:
- Dust Man's stage is the longest of the Robot Master stages, with lots of tricky platforming and Spikes of Doom.
- The Wily Station stage is far and away the longest stage in the game, with no breaks to be found at all. Even worse is that another Giant Suzy (previously fought as a boss between each set of Robot Masters) has to be fought near the end.
- Nintendo Hard: Oh yes. Though the Mega Man series is this in general, III is often considered to be the hardest game in the Game Boy series, if not the franchise itself. It's usually considered a toss-up between this game, which has extremely tough level design bordering on outright Platform Hell in the second half, and Dr. Wily's Revenge, which is shorter and has slightly easier levels, but no Charge Shot, no energy tanks, very few item drops, and no Rush equivalent until you get to the first Wily stage.
- Orbiting Particle Shield: The Skull Barrier makes its return, but is significantly stronger than it was in Mega Man 4 as it now takes three hits from projectiles (not just one) before disappearing.
- Rearrange the Song: After the mixed (to say the least) reception of the previous game's almost entirely original soundtrack, this game went back to the Dr. Wily's Revenge approach and mostly used remixed music from the NES entries, with a few new original themes along the way.
- Recurring Boss: Giant Suzy antagonizes Mega Man twice; first at the start of the Wily Castle (before encountering the second set of Robot Masters), and again near the end of the Wily Station.
- Strictly Formula: By now the Game Boy sub-series was settling into a pretty recognisable format (despite the lack of an Astral Finale that was present in the other games), though the following game would shake it up a little (and Mega Man V would shake it up a lot).
- Supervillain Lair: The Wily Castle makes its return, though in a unique twist, the second set of Robot Master stages are all set inside the castle itself.
- Unique Enemy: In Wily Station, a Neo Metall from Mega Man 2 and an original Metall from Mega Man appear. Those two are the only ones of their respective kind in the game.
- Villain: Exit, Stage Left: After his defeat, Dr. Wily escapes Mega Man via a conveniently-placed hatch in the floor. His UFO escapes the self-destructing Wily Station, only to drop into the sea with a skull-shaped mushroom cloud.