Below is a list of Special Weapons obtained by defeating the Robot Masters in the game Mega Man 9, how Mega Man can use them to his advantage and the Robot Master/boss who is the most vulnerable to them.

Special Weapons
Name Black Hole Bomb
Robot MasterGalaxy Man
Abilities Creates a black hole that pulls nearby enemies and enemy fire into it.
Against Jewel Man
Name Concrete Shot
Robot MasterConcrete Man
Abilities Fires a small glob of concrete that solidifies into a solid block when it comes into contact with the ground or a wall. This weapon is short-ranged, but it is quite powerful.
Against Galaxy Man
Name Hornet Chaser
Robot MasterHornet Man
Abilities Shoots out hornets to sting enemies and/or to retrieve items.
Against Splash Woman
Name Jewel Satellite
Robot MasterJewel Man
Abilities When activated, Mega Man will have four jewels orbiting him. When the fire button is pressed while the shield is up, the shield is launched as a projectile in the direction Mega Man is facing.
Against Plug Man, Fake Man
Name Laser Trident
Robot MasterSplash Woman
Abilities Shoots out trident heads that can break through concrete blocks.
Against Concrete Man
Name Magma Bazooka
Robot MasterMagma Man
Abilities Instead of Atomic Fire's single shot, this chargeable weapon fires three flame shots: one diagonally up, one diagonally down and one straight forward.
Against Hornet Man
Name Plug Ball
Robot MasterPlug Man
Abilities Shoots out spark balls that fall directly down and then roll across the ground. Any enemies that come into contact with them are electrified.
Against Tornado Man
Name Tornado Blow
Robot MasterTornado Man
Abilities Like Rain Flush, this is a weapon that reaches all over the screen, blowing away enemies and projectiles or damaging them.
Against Magma Man
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