Blaster

Blaster (ブラスター), known as Beak in some English sources, is a wall-mounted gun with a beak-like armored shell that opens and closes. They are indestructible when closed, and shoot in four different directions when open.

Mega Man
Blasters appear in Cut Man's stage, Bomb Man's stage and the final stages.

Mega Man: The Wily Wars
Blasters appear in the stages of Buster Rod G and Mega Water S.

Mega Man Network Transmission
Blaster appears as a virus in the game. They shoot in the same pattern as the original Mega Man series counterpart.

Other media
Blaster appeared in Captain N: The Game Master and the Rockman manga.

While absent in Mega Man Megamix, Blaster (misnamed as Bluster) is listed as one of the robots under Cut Man's control.

Similar enemies
Enemies similar to Blaster.
 * Wall Blaster
 * Wall Blaster 2