As one of the tougher games in the series, knowing the correct order to fight the bosses in Mega Man 3 is critical. Although you can go through the game however you'd like, I outlined the best order here along with strategies and the most effective boss weaknesses.
Mega Man 3 Boss Order / Weaknesses
I'll cover every single boss in the entire game in-depth below but for now, here is the order to fight the Robot Masters of Mega Man 3:
- Magnet Man / Mega Buster (Spark Shock for 2nd encounter)
- Hard Man / Magnet Missile
- Top Man / Hard Knuckle
- Shadow Man / Top Spin
- Spark Man / Shadow Blade
- Snake Man / Shadow Blade (Needle Cannon for 2nd encounter)
- Gemini Man / Search Snake
- Needle Man / Gemini Laser
You'll end up facing Proto Man as a mid-boss in certain levels (Magnet Man, Hard Man, and Shadow Man) and to fight him, jump over when he runs, run under when he jumps, and keep shooting. He's most weak against Hard Knuckle (HA) but he's easier to hit with Magnet Missile (MA) so I recommend using that after you unlock it. We'll just use the trusty Mega Buster in the first encounter, though.
Magnet Man Mega Buster (P)
The first boss we'll take on is Magnet Man. He hops around the boss room so keep shooting the Mega Buster, run underneath him when he takes a big jump which should be every second hop, dodge the magnets which descend when they cross your path, and run away when he magnetizes himself. If you can keep at it and get over this hurdle, the rest of the Robot Masters will be much easier.
Hard Man Magnet Missile (MA)
This boss is fairly simple because his weakness (Magnet Missile) should home in on Hard Man so all you need to do is shoot them in his direction while running underneath him when he jumps and jumping over his fist projectiles. He'll go down after 7 hits. 🧲
Top Man Hard Knuckle (HA)
Next, the boss to beat is Top Man. Leap over his tops when they fly towards you then jump over him after he spins around and charges at you but be careful because he spins in-place for quite a while. Fire Hard Knuckles his way whenever you get the chance; except they bounce off him while he's spinning so time your shots appropriately. 4 hits are all it takes to defeat this tricky Robot Master. 🤛
Shadow Man Top Spin (TO)
Fighting Shadow Man should make for one of the easiest bosses in Mega Man 3 as all you need to do is use Top Spin by jumping then tapping the attack button while trying to stay close to him without colliding into him so you don't take damage. All it takes is 4 bumps before he bites the dust. After this quick fight, you'll unlock Rush Marine for your efforts. 😊
Spark Man Shadow Blade (SH)
As with the typical uneven-floor boss, Spark Man is pretty easy. Just shoot Shadow Blades at him which he is weak against; they can thankfully go through walls and you can also shoot them up as well as at 45° angles. As soon as you hit him 7 times, he'll be a goner.
Snake Man Shadow Blade (SH)
The 3 remaining bosses aren't particularly weak against any weapons that we have but Snake Man is the easiest so let's defeat him next. Shadow Blades are fairly strong against him and work well throughout his stage, too, so keep shooting him and don't forget that you can launch them up and at angles whenever he jumps around; another uneven-floor boss falls victim to good old Shadow Blades! 😄
Gemini Man Search Snake (SN)
The next boss is Gemini Man whose weakness is Search Snake as it causes a lot of damage and can scale walls which is a nice bonus. Anyway, Gemini Man jumps around all herky-jerky like so keep unleashing Search Snake so that they travel along the floor and walls into either Gemini Man clone. The fight won't last long with only 3 snakes being required to beat each clone. 🐍
Needle Man Gemini Laser (GE)
The final robot master that we'll beat following this order is Needle Man who is actually easy as his weakness is Gemini Lasers which will bounce off the back wall and probably hit him if they miss him at first so all you need to do is shoot 4 of those suckers at him and he'll head straight to the scrap yard. Oh, and you'll get Rush Jet after your victory which is awesome! 😁
Spark Man stage - Metal Man Magnet Missile (MA)
Okay, it's time to defeat copies of the Mega Man 2 bosses via the dastardly Doc Robot; how nostalgic! First, Metal Man's weakness is Magnet Missile which makes the boss fight very short and sweet as you only need to attach 7 magnets to him. 🧲
Spark Man stage - Quick Man Gemini Laser (GE)
Considering Quick Man jumps around a lot, it's a good idea to use Gemini Lasers as he's somewhat weak against them and they'll reflect all over the screen which is a nice bonus. This is probably the hardest of the Doc Robot incarnations so don't be afraid to use an E-Tank!
Needle Man stage - Air Man Spark Shock (SP)
Although Air Man is equally weak against Magnet Missiles, Spark Shock has more ammo so leap over or slide under the whirlwinds that the boss launches, run underneath him when he changes sides, and keep shooting until he's ready for the junk heap.
Needle Man stage - Crash Man Hard Knuckle (HA)
It's a bit tricky to hit Crash Man with the Hard Knuckle because he jumps everywhere and that weapon is slow to launch. However, he's super-weak against it as you only need to land 4 hits so keep dodging his attacks and fire fists consistently to knock him out fast.
Gemini Man stage - Flash Man Needle Cannon (NE)
Flash Man jumps around his uneven stage a lot but he's very easy to beat as his weakness is the Needle Cannon which fires super-fast so you should make short work of him. It's refreshing to fight such an easy boss every once in a while, isn't it? 😅
Gemini Man stage - Bubble Man Shadow Blade (SH)
This boss fight will likely give you flashbacks to Mega Man 2 because you'll use Shadow Blade which is very similar to Metal Blade and you can shoot it up and at angles as well. I guess things won't go as swimmingly for Bubble Man as he thought they would.
Shadow Man stage - Wood Man Needle Cannon (NE)
Just like in Mega Man 2, leap over Wood Man's tossed leaf shield, try to stay between the falling leaves, and fire Needle Cannon at him when his shield is down which is one of his weaknesses and definitely the fastest way to end the fight.
Shadow Man stage - Heat Man Top Spin (TO)
You have a choice with Heat Man: his main weakness is Top Spin but using it is tricky so you can use Shadow Blade instead if you prefer. Either way, dodge his fireballs and jump over him when he dashes then attack aggressively. That's all for these revisited bosses! 😁
Break Man Mega Buster (P)
The only weapon that's effective against Break Man is the good old Mega Buster so fight him as you did Proto Man and it'll be over soon.
Kamegoro Maker Shadow Blade (SH)
First, in order to break the walls throughout the stage before the boss, use Hard Knuckle. Anyway, to beat Kamegoro Maker, simply fire Shadow Blades up at the turtles when they spawn and it'll be defeated once you destroy 5 of them. Pretty easy, right? 🐢
Yellow Devil Mk-II Hard Knuckle (HA)
This one can be tricky. For an easier time, deploy Rush Jet and hover to the top of the screen while the blocks move into place. Alternately, run to the middle of the screen then the blocks will hurl towards you in the following row order starting from the floor (jump over the 1s, slide under or jump over the 2s, and stand still so the 3s, 4s, and 5s can fly overhead): 1, 5, 2, 1, 4, 3, 2, 5, 4, 2, 3, 4, 3, 1, 5, 3, 4, 5, 1, 3, 2, 2, 4, and 5. Try to get 2 Hard Knuckle shots in before the boss breaks up each time which will require spot-on timing. He'll always follow the mentioned pattern but will eventually break up into bouncing blocks so try to run or slide under those.
Mega Man Holograms Top Spin (TO)
Here's another tricky boss! You have to attack the correct Mega Man which has the classic warp animation when it emerges while the other 2 merely appear out of thin air. That being said, you can end this fight right away by using Top Spin on the top Mega Man right when the fight starts. Considering the boss doesn't have any invincibility frames, its health will deplete very quickly so be aggressive.
Robot Masters Revisited
It's time to fight all of the Mega Man 3 Robot Masters again. Considering the order that we originally fought them in, we'll use a couple of different weapons this time; namely, Spark Shock against Magnet Man and Needle Cannon against Snake Man. That should make things a bit easier but these bosses can still be tough so stay on your toes! Oh, and just so you know; the boss doors starting from the top-right and going clockwise are: Snake Man, Spark Man, Shadow Man, Top Man, Hard Man, Gemini Man, Magnet Man, and Needle Man.
Wily Machine 3: Part 1 Spark Shock (SP)
This first phase is probably the easiest boss in the whole game. Just shoot 4 Spark Shock shots at the turret that's underneath the boss.
Wily Machine 3: Part 2 Hard Knuckle (HA)
The final half of Wily Machine 3 can be taken down with another 4 shots but this time, its weakness is Hard Knuckle. You have to time your shots very well, though, because he dips down for an exceptionally short time. I jump and shoot as soon as the 2nd leg is about to land which usually does the trick so keep a keen eye on its legs which is surprisingly the key to victory with this Wily contraption.
Gamma: Part 1 Hard Knuckle (HA)
Use Rush Coil to jump to the right ledge then shoot 4 Hard Knuckles at Gamma's head to quickly end this first phase. That was easy! 😊
Gamma: Part 2 Top Spin (TO)
Okay; time to get serious! For the very final boss, hop up onto the platform next to the helmet with Dr. Wily in it then jump and use Top Spin on Wily to put him out of his misery. Make sure to center your attack to maximize damage and leap over to him after he fires a shot at you from Gamma's mouth so he doesn't snag you mid-jump. Don't worry; the horn spikes won't hurt you. Also, deploy your Top Spin above Wily's window so you don't get hurt by it before you can land your attack. Congratulations on beating Mega Man 3! 🏆