Megaleg is a giant machine that first appeared in the galaxy "Bowser Jr.'s Robot Reactor". Megaleg is a humongous machine which is powered by a Grand Star and has just one weakness. At the top of it is a spot that if hit by a bullet bill will damage it, while more the spot is damaged, more the difficulty will increase. Mario must avoid the numerous bullet bills coming after him and hit them to the spot. Once it is destroyed, Megaleg will blow up, while the Grand Star on it will be released for Mario.