Ice Slasher

Ice Slasher (アイススラッシャー) is Ice Man's Special Weapon. It 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 crystallises to form a projectile. Not only is this Fire Man's weakness, but Mega Man can also freeze the flame geysers in his stage and in the first level of Dr. Wily's base to use as steps.

Damage Data Chart
Known damage values for the original Mega Man. Known damage values for Megaman: Dr. Wily Revenge.

Bosses weak against Ice Slasher

 * Fire Man: Mega Man, Mega Man: Dr. Wily's Revenge and Mega Man: Powered Up
 * Flash Man: Mega Man: Dr. Wily's Revenge
 * Mega Water. S: Mega Man: The Wily Wars
 * Fire Snakey: Mega Man: The Wily Wars
 * Heat Man: Mega Man: The Power Battle

Bosses immune to Ice Slasher

 * Bomb Man: Mega Man
 * Cut Man: Mega Man and Mega Man: Dr. Wily's Revenge
 * Elec Man: Mega Man and Mega Man: Dr. Wily's Revenge
 * Guts Man: Mega Man
 * Yellow Devil: Mega Man
 * Copy Robot: Mega Man
 * Enker: Mega Man: Dr. Wily's Revenge
 * Heat Man: Mega Man: Dr. Wily's Revenge
 * Wily Machine: Mega Man and Mega Man: Dr. Wily's Revenge
 * Wily Machine (2nd Form): Mega Man: The Wily Wars

Other media
Mega Man uses the Ice Slasher in the Mega Man animated series. However, it differs from its in-game depiction in the fact that it takes the form of a beam of shatteringly cold energy, being able to freeze almost anything within a few seconds of exposure.

At one point, when Ice Man himself used it in Episode 7, he froze Rush with it before kicking him, shattering him to pieces. He also used it to provide the icy armour for the "Ice Bots" he used later to attack Doctor Wily and Air Man after they landed in the city.

Curiously, it was not referred to by its actual name, but was referred to as the "Freeze Ray" by Ice Man when he calls for Air Man's help after Mega Man copies it from him.