Below is a list of Special Weapons obtained by defeating the Robot Masters in the game Mega Man 4, how Mega Man can use them to his advantage and the Robot Master/boss who is the most vulnerable to them.

Special Weapons
Name Dive Missile
Robot MasterDive Man
Abilities Fires missiles that home in on the target.
Against Drill Man
Name Drill Bomb
Robot MasterDrill Man
Abilities Can pierce through barriers. Mega Man can set off an explosion when pressing the attack button after a drill is fired.
Against Toad Man, Wily Machine No. 4
Name Dust Crusher
Robot MasterDust Man
Abilities Sends a ball of debris that can split diagonally into four pieces when it hits something solid.
Against Skull Man, Cossack Catcher
Name Flash Stopper
Robot MasterBright Man
Abilities Unlike Time Stopper, Flash Stopper stops time for a limited time, but allows Mega Man to shoot enemies while they are stopped.
Against Pharaoh Man
Name Pharaoh Shot
Robot MasterPharaoh Man
Abilities Charging it forms a large fireball over Mega Man's head, which can damage enemies who comes into contact with it without draining the weapon's energy or canceling the charged attack.
Against Ring Man
Name Rain Flush
Robot MasterToad Man
Abilities Creates an acid rain storm that affects all things vulnerable to it, and can hit several times before disappearing.
Against Bright Man
Name Ring Boomerang
Robot MasterRing Man
Abilities Has a somewhat limited range and boomerangs back. Can do multiple hits if aimed correctly.
Against Dust Man
Name Skull Barrier
Robot MasterSkull Man
Abilities Creates a skull-shaped energy shield around the user, protecting him from attacks. Unlike Leaf Shield, Mega Man can walk around while the shield is active.
Against Dive Man
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