The Mega Man games are renowned for their manic platforming and difficult boss fights, which truly demand a ton of patience and skill from the player. The stages are often hard enough in their own right, but most players have had nightmare experiences with many of the bosses, especially when using only the Buster.
The original three games - pre-charge shot - are often considered the most challenging games in the series, but the Mega Man X games renewed the difficulty by forcing players to find hidden upgrades within stages to even stand a chance against the harder bosses. Though every player will have a different experience, certain bosses are infamous for being a total pain in the butt to take down.
10 Quick Man: Can't Sit Still
On the whole, Mega Man 2's levels are generally harder than the bosses, but Quick Man is one nasty boss to run into before knowing his weakness. First, the player needs to get through one of the toughest stages in the game, dodging a gauntlet of lasers that incinerate the player instantly. The Time Stopper power-up can keep the lasers at bay, but that is also Quick Man's weakness, so using it up brings the player's chances of beating the boss to almost zero.
Quick Man - true to his name - isn't one to take much of a breather, and the hectic fight is nearly impossible for the average player without the time stopper. Though he can be easily taken out with the Time Stopper, newer players won't necessarily know this.
9 Sting Chameleon: Strike While You Can
The original Mega Man X is a pretty well-balanced game that lands on the trickier side of the spectrum. All of the bosses can be challenging, especially without armor upgrades and power-ups, but Sting Chameleon beats out the competition based on how hard he is to hit, even with access to his weakness, Boomerang Cutter.
Sting Chameleon disappears and reappears around the stage, and the player only has a brief moment to hit him. It's easy to miss with the Boomerang Cutter, and Sting Chameleon's attacks have a lot of range. It is a long, drawn-out battle that feels harder than the other seven robot masters.
8 Block Devil: A New Take On An Old Foe
Mega Man fans have learned that the name "devil" for any boss implies an excruciating amount of pain is headed their way. Mega Man 10's Block Devil is true to Devil form and sends patterns of blocks flying from the walls to form a giant block, before the eye - it's the only vulnerable point - appears. Worse yet, the player can fall into pits, and there is no completely safe place to stand. The player has a narrow window of time to hit the Block Devil before being required to dodge the blocks again and survive for another chance.
The only thing that makes this battle manageable is that the boss has multiple weaknesses. The Rebound Striker and Lightning Bolt both do a lot of damage to Block Devil. Nevertheless, without energy tanks, this boss fight would take even skilled players many attempts to conquer.
7 Slash Man: An Unrecognizable Pattern
Mega Man 7 has a few tough bosses, but Slash Man will give players the most trouble. It's very tricky to even hit him with his weakness, so some payers will stick to the Buster. He will jump around the stage and lunge at Mega Man, and when he disappears, rotten eggs (nobody seems to know what these actually are) fall from the ceiling.
This is a tedious fight that takes a tremendous amount of patience, but players with E-tanks will likely be able to keep healing and tough it out, not that that is a very satisfying victory.
6 Blast Hornet: A Serious Handache
Mega Man X3 has some of the most inconsistent boss difficulty in the franchise, but the hardest Maverick is undoubtedly Blast Hornet. Players will need an extraordinary amount of finger strength and dexterity to overcome this boss. Blast Hornet likes to send out droves of small hornets that hover around the stage, all the while Blast Hornet bounces around and stings X.
What makes this fight so hard is that players using the Buster will need to use the charge shot to get rid of the smaller hornets and deal significant damage to the boss. However, at the same time, they will constantly need to move around and dash away from Blast Hornet. It is some serious finger gymnastics that feels both mentally and physically exhausting.
5 Needle Man: Each Hit Is Almost A Knock-Out
Mega Man 3 has its fair share of hard bosses with Snake Man, Shadow Man (who gives the player one of the lamest power-ups in the franchise), and Needle Man. A lot of players will find Shadow Man to be more difficult, but it's a toss-up. Needle Man has a less consistent pattern than Shadow Man, and his attacks deal heavy damage. Just a few hits in this fight and Mega Man is done.
Having the Top Spin makes this fight much easier, but Needle Man jumps around and shoots needles, which are hard to dodge since they are fired diagonally. Just learning the pattern won't help you win this fight until you can dodge his needles like a pro.
4 Infinity Minjinion: Claustrophobia
Infinity Mijinion isn't just the hardest Maverick in Mega Man X6, he might be the hardest maverick in the entire X series. His stage is bad enough, but after barely surviving the stage and most likely failing to save Reploids, the player is greeted by one of the most annoying bosses in Mega Man history.
Infinity Mijinion can send out seemingly infinite bubbles that take up almost the entire screen. They are very hard to dodge and make landing a hit on the boss that much harder. While dodging the bubbles, Infinity Mijinion will also move around and fire small shots at Mega Man.
3 Kaiser Sigma: A Mix of Every Mega Nightmare
This is the hardest Sigma fight in the entire Mega Man X franchise. It's a three-part battle, and none of the forms are particularly easy. Players without stored health and full armor upgrades stand almost no chance. The first form is fast-paced, and any hit will do heavy damage to X. You need to beat this form without taking any damage to really stand a chance.
The second form is where the real fun begins. Kaiser Sigma hovers around, and his only weak spot is his head. You'll need to charge your shot and climb the wall while dodging a plethora of projectiles just to land a hit. Survive this grueling fight and you will be treated to a tough platforming section where any fall from the wall ends in instant death, requiring you to restart the entire boss battle.
2 Yellow Devil: The Original Unforgiving Boss
Yellow Devil might be the most infamous boss in Mega Man history. Almost every Mega Man fan complains about this boss, and it's a huge spike in difficulty compared to all the previous bosses. He only has a small weak point that disappears almost as soon as it appears. Between reappearing, you need to dodge blocks that randomly fly across the screen and deal massive damage.
This was the very first Mega Man game, and it didn't have E-tanks, so there is no easy way to heal or win a battle of attrition. Players who are really struggling can take advantage of a glitch. Shoot Thunder Beam at the eye and press the pause button rapidly. If done successfully, one lightning attack will hit the eye multiple times. Those wanting a fair fight will have a long day of work ahead of them.
1 Wily Capsule: Impossible to Hit
This is it, the hardest fight in Mega Man history, and it's fitting that it's Mega Man's arch-nemesis Dr. Wily. The Wily capsule is the second form of the final fight in Mega Man 7. Players taking this on hopefully beat the first form without taking any damage, otherwise, this might be a lost cause.
The reason this fight is so difficult is that it is almost impossible to hit the Wily Capsule with its weakness since he spends so much time in the air. Most players will revert to the Buster, which only deals a nominal amount of damage. Even then, you'll have to pray that Wily doesn't appear on the top of the screen too often, where the Buster cannot hit him at all. All in all, this boss requires some luck and a ton of patience.