Pharaoh Wave

Pharaoh Wave (ファラオウェーブ) is Pharaoh Man's Special Weapon in Mega Man 2: The Power Fighters.

Mega Man 4
While Pharaoh Wave isn't mentioned in the game, one of Pharaoh Man's attacks is similar to this weapon, firing one energy wave straight forward. However, Mega Man can't obtain it from him, obtaining Pharaoh Shot instead.

Mega Man 2: The Power Fighters
Pharaoh Wave replaces Pharaoh Shot as the weapon obtained by the player in Mega Man 2: The Power Fighters. It is obtained by the player that takes the Special Weapon Item after defeating Pharaoh Man in the "Recover the new parts!" course. When used by Pharaoh Man and the playable characters, it releases waves, one forward and one backwards. Pharaoh Wave is Gemini Man's weakness, and can hit the two Gemini Men at the same time.