Below is a list of Special Weapons obtained by defeating the Robot Masters in the original Mega Man game, how Mega Man can use them to his advantage and the Robot Master/boss who is the most vulnerable to them.

Special Weapons
Name Fire Storm
Robot MasterFire Man
Abilities Shoots a fireball, and has a temporary shield effect.
Against Bomb Man
Name Hyper Bomb
Robot MasterBomb Man
Abilities Throws bombs in a small arc with a slight delay between when a bomb is thrown and when it explodes, but with a decent enough explosion that damages or destroys anything within the blast.
Against Guts Man
Name Ice Slasher
Robot MasterIce Man
Abilities Takes the form of an arrowhead-shaped blade of ice that can either damage or freeze enemies. It is produced via a blast of super-chilled air laced with liquid nitrogen, which then crystallizes to form a projectile.
Against Fire Man
Name Rolling Cutter
Robot MasterCut Man
Abilities Takes the form of a large pair of extremely sharp scissor blades that are thrown like boomerangs, flying in front of Mega Man in a teardrop-shaped pattern before returning to him. Can also go through walls.
Against Elec Man
Name Super Arm
Robot MasterGuts Man
Abilities Mega Man can walk up to certain blocks, and if they can be picked up by the Super Arm, they will flash. Press the attack button to pick them up and press it again to throw them. If there is not enough room available to create an arc, or if/when they land on the ground, the blocks will scatter.
Against Cut Man
Name Thunder Beam
Robot MasterElec Man
Abilities Shoots three long electrical bolts in different directions, one forward, one straight up, and one straight down. Because of the three-way spread and its ability to go through enemies, the Thunder Beam is considered the most powerful weapon in the game.
Against Ice Man
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