Mega Man 3, known as Rockman 3 in Japan, is widely considered to be one of the best games in the Mega Man franchise. There are eight new robot masters to battle named Spark Man, Snake Man, Needle Man, Top Man, Shadow Man, Magnet Man, Gemini Man, and Hard Man. There is also the addition of a new move which gives Mega Man the ability to slide, allowing him to reach new places and avoid enemies. Mega Man 3 introduced Mega Man's robotic dog, Rush in the second iteration, which replaced the powerup's "1, 2 and 3" from Mega Man 2. The game removed Mega Man's ability to create a moving platform on a wall, replacing it with the Rush Submarine. The game has a few twists, such as once defeating the eight new robot masters one has to go defeat the original eight robot masters from Mega Man 2 in a powered up state. Mega Man 3 is the first Mega Man game to feature Mega Man's brother, Proto Man.
Series creator, Keiji Inafune, considers this to be one of his least favorite Mega Man games, in part because of the slide maneuver.
The story takes place in the year 200X, when a reformed and nice Dr.Wily has set out to work on project "Gamma", a peace keeping robot, with Dr.Light. Unfortunately, the eight robot masters the two had built to maintain Gamma go berserk, and take off with the power crystals. Mega Man is called once again to save the day, retrieving each crystal from one of eight mining planets deep in space.
At the same time, Mega Man's brother and Dr.Light's first creation, Proto Man, has returned after an entire year in hiding, hoping to train Mega Man on a number of stages, preparing him for the fight ahead. His final appearance as a foe in the game comes before the Wily levels, when he shows up as "Break Man".
Mega Man takes on each of the eight robot masters, then returns four of their realms later to defeat reincarnations of the robot masters from Mega Man 2. Once he has done this, he travels to Dr.Light's lab where Dr.Light informs him that Dr.Wily has stolen Gamma! Mega Man takes off to face Gamma and defeats Gamma and Dr.Wily. Just before the roof collapses and crushes him, he is taken to safety by Proto Man.
Mega Man 3 retains the gameplay formula the Mega Man games are so well known for. The player can choose to take on the eight robot masters in any order they choose. Each robot master is weak to another's special weapon, and it is up to the player to experiment and discover what will best work against his foes. Mega Man begins with only his mega buster weapon, but as he progresses, he will earn new weapons from each robot master that he defeats. Mega Man 3 is also known for the addition of the slide move, which became a staple of later iterations. The game also introduces a new Rush power, the Rush sub, which allows Mega Man to travel through water.
Each stage in the game employs a variety of new obstacles which Mega Man must conquer. These include low walls that must be slid under, tricky jumps, and the infamous disappearing block sections.
Mega Man 3 is host to an interesting glitch in which Mega Man can leap the height of the entire screen if players plugged in a second NES controller and held down RIGHT on its d-pad. The actual jumping ability was probably a hidden cheat; the actual glitch comes in handy when the player dies by falling into a bottomless pit. With proper timing, players could then attempt to jump out of the pit using the cheat, sending Mega Man back into the playing field with a completely empty life bar. The result is an invincible Mega Man; while he still reels back from contact, he is able to take an infinite amount of punishment in this condition. Two caveats: (a) Mega Man can no longer fire off his Mega buster, and must make use of his nemeses' weaponry--and if he is out of "ammo" in this condition, he's practically useless on the offensive end; (b) Mega Man is still vulnerable to spikes. Also, grabbing a life powerup while in this state will fill up some of Mega Man's energy bar, making him once again vulnerable to attacks (and possibly very near death, if a small life powerup was picked up).
Below are the Robot Masters unique to Mega Man 3. Like all classic Mega Man games, Mega Man gains each robot master's weapon when they are defeated. In an oddity for the series, the vulnerability relationships in Mega Man 3 aren't entirely circular: That is, there is not one solitary sequence for defeating the robot masters from beginning to end with the luxury of having the appropriate weapon (past the first fight). In other words, at some point even after your first boss fight, players will have to walk into a robot master encounter with a sub-optimal weapon. Note that in Dr. Wily's castle, players encounter 8 additional Robot Masters from Mega Man 2 but they do not have full stages, nor do they have useable weapons.
Weak Against: Hard Knuckle
Main attacks: Top Man will throw out multiple tops that hover in the air before zoning in on Mega Man in a straight line. He will then spin (pirouette, really) and propel himself across the screen at Mega Man.
Weapon: Top Spin - Used by jumping and using the weapon in mid air. Mega Man will spin like a top and damage any enemy he hits.
Color Scheme: Grey and Pink.
Weak Against: Magnet Missiles
Main attacks: Hard Man will throw out consecutive Hard Knuckles that angle towards Mega Man. He will also leap high into the air; upon crashing down, he will cause an enormous quake that will stun Mega Man if he's on the ground when it occurs.
Weapon: Hard Knuckle - Shoots a fist-shaped missile that moves slowly, but does big damage. Can destroy certain walls.
Color Scheme: Navy Blue and Grey.
Weak Against: Shadow Blade
Main attacks: Spark Man will leap around and try to collide with Mega Man. He also generates a large spark and tosses it in Mega Man's general direction. His lair is not flat, making it difficult to avoid him.
Weapon: Spark Shock - Fires a large ball of electricity. Easy to use because of the large size of the projectiles.
Color Scheme: Salmon and White.
Weak Against: Search Snake
Main attacks: Gemini Man will split in two, and the pair will work in a quasi-juggling pattern: one running along the ground from left to right, trying to collide with Mega Man, and one leaping in the air from right to left. When the airborne clone hits the ground, the two exchange roles. The Gemini Man clones will also eventually merge and the one will fire his reflective Gemini Laser.
Weapon: Gemini Laser - Fires a blue laser that can bounce off walls. Can continue after hitting an opponent and hit more than once.
Color Scheme: Light Blue and White.
Weak Against: Gemini Laser
Main attacks: Needle Man leaps high in the air and fires off consecutive needles at different points during his descent. He will also thrust his needle-ridden "hair" Mega Man's way.
Weapon: Needle Cannon - Fire a barrage of needles. Can rapid fire by holding down the fire button.
Color Scheme: Brown and White.
Weak Against: Spark Shock
Main attacks: Magnet Man leaps high in the air and fires off consecutive magnet missiles, which take a right angle downwards depending on where you're standing at the time. He will also attempt to pull Mega Man into his magnetic field to cause massive damage.
Weapon: Magnet Missiles - Shoots a magnet that can move up or down to "track" enemies to a certain degree.
Color Scheme: Red and Grey.
Weak Against: Top Spin
Main attacks: Shadow Man uses a combination of short hops, high jumps and slides to collide with Mega Man. He will also throw out his Shadow Blades at seemingly random intervals.
Weapon: Shadow Blade - Shoots a ninja star that goes straight but boomerangs back. Limited range, but can be fired up or down as well as forwards.
Color Scheme: Purple and Lilac.
Weak Against: Needle Cannon
Main attacks: Snake Man will fire off several Search Snakes that probe the ground and walls, making it difficult for Mega Man to maneuver around Snake Man's angular lair. At the same time, Snake Man will use the make-up of his lair to jump around and attempt to collide with Mega Man.
Weapon: Search Snake - Shoots a snake-like projectile that travels along the floor. Can even move up or down walls.
Color Scheme: Green and White.
In addition to the Robot Master's weapons, Mega Man can summon the robotic dog, "Rush". Rush can perform a variety of tasks to aid Mega Man, effectively taking the place of the items from previous Mega Man games.
- Rush Coil: Rush becomes a spring board that will launch Mega Man into the air. Available from the start.
- Rush Marine: Rush becomes a submarine that Mega Man can enter and use to traverse bodies of water. Obtained after defeating Shadow Man.
- Rush Jet: Rush becomes a jet board that Mega Man can ride to traverse large pits. Obtained after defeating Needle Man.
- Mega Man 3 marks the first time that the series has deviated from the theme music that plays when players confirm the selection of a boss robot. The recognizable theme from the original Mega Man and Mega Man 2 would return in Mega Man 4, but would change again for Mega Man 5 and Mega Man 6.
- Mega Man would previously storm Dr. Wily's castle immediately after the demise of the final robot master in Mega Man and Mega Man 2. However, Mega Man 3 started the trend of delaying this inevitable assault by one stanza. Here, Mega Man hasto fight through the eight reincarnations of the Mega Man 2 robots as well as face off with "Break Man" before heading to Wily himself. (In subsequent NES games, Dr. Cossack, Proto Man and Mr. X would masquerade as the "lead villains" before Dr. Wily was unsurprisingly revealed as the true mastermind behind all of the events that were taking place.)
- Mega Man 3 marks the franchise debut of the aforementioned Proto Man as Mega Man's brother.
- Mega Man 3 changed the sound effect, in relation to its predecessors, that plays when Mega Man lands on the ground from a jump or a fall.
- Mega Man 3 changed the sound effect, in relation to its predecessors, that plays when Mega Man is hit.
- Mega Man 3 changed the sound effect and appearance, in relation to its predecessors, of Mega Man's explosion--as well as those of other robot masters--upon death. The "bubbles" that burst outward travel faster, and sport a cleaner, larger look. In addition, defeated robot masters explode with the same white bursts as Mega Man does; in previous games, those bursts are tinged with the color scheme of the robot master.
- Mega Man 3 increased the speed at which Mega Man climbed ladders from its predecessors.
- Mega Man 3 used a very slightly less abrasive sound effect for recharging life meters from its predecessors.
- Mega Man 3 changed the way Mega Man's mega-buster shots collided with boss characters. In previous entries, the sound effects were employed such that Mega Man's shots wouldn't register as a "hit" while the boss character's hit burst appeared on the screen. (About the "hit burst": every time players hit a robot master with a shot, a white flash would emanate from its body, indicating a successful hit.) In Mega Man 3, the sound effects made it sound as if every shot fired came in contact with a robot master, instead of having some shots "pass through." However, as in previous games, only shots that resulted in the hit burst would deplete the boss characters' energy meter.