King Plane (キングプレーン Kingu Purēn) is the second boss from the second fortress stage in Mega Man & Bass. It is a giant plane that is fought on a series of small, floating platforms that move out of the screen, forcing the player to move from one to another. It reappears later, fusing with King into Jet King Robo in a final effort to defeat Mega Man and Bass.
- It shoots bubbles at the player. However, the bubbles are not harmful but have either a health item, a weapon capsule, or a blinder in it. If the player jumps on the former two items, the player will be able to use them. If the player contacts the blinding item, however, the whole screen will flash white, leaving the player temporarily blinded.
- It shoots out a fist that destroys the platforms that are in its path. It takes quick movement to dodge or use the Lightning Bolt to hang in the air temporarily for timing the platform that the fist didn't target.
- It shoots an undodgeable ray of light. The player has to damage its core to stop it from using the attack.