Sea Mine

Sea Mine (機雷 / キライ) is a mine obstacle in Mega Man 4 and Mega Man III. They only appear in Dive Man's stage, appropriately enough. They bob up and down, and are invincible to attacks. They explode after a short while when Mega Man draws near.

Trivia

 * "Kirai" is Japanese for "naval mine".
 * In Mega Man 2: The Power Fighters, Dive Man is able to release blue mines from his body resembling this mine, but these can be destroyed by Special Weapon.