The Power of Junior

The Power of Junior is the last level in Bowser's Castle (East) in the Bowser Jr.'s Journey mode of Mario & Luigi: Bowser's Inside Story + Bowser Jr.'s Journey

Overview
After Bowser Jr. has taken on all the captains at least once, Captain Goomba rallies the other captains for Bowser Jr. to take on all four of them at once as one final test, with the addition of King Bob-omb as a "game-changer". If King Bob-omb is not defeated in under 90 seconds, he will explode and instantly defeat any surviving allies.