Ballonboo

Ballonboo (バルンブー) is a balloon enemy from Mega Man 9 that appears in Tornado Man's stage. It probably used to collect weather data before being monified by Dr. Wily.

Normally, it will just float up and down and try to fire pellets at the player. However, if the player fires at the balloon, it will burst out of control and attempt to tackle him. Depending on the size of the screen, the Ballonboo may attempt to tackle more than once. If Mega Man shoots the robotic face, it will explode sending the remaining balloon to the sky.

Trivia
Its name is derived from the word balloon (バルーン).