Super Peach's Castle of Fury

Super Peach Castle is a portion of Peach's Castle in the game Mario & Luigi: Bowser's Inside Story. Bowser must become giant to fight it. When the incomplete Dark Bowser exits Bowser, Dark Fawful arrives in front of Bowser and taunts Bowser while saying "SUPER PEACH'S CASTLE OF FURY!". Then the castle transforms into a Mecha of some sort and crushes Bowser. Afterwards Mario, Luigi and Starlow go to the Rump Command and make Bowser giant again. He then fights the castle.

Super Peach Castle starts off the battle by creating a black hole that forms behind Bowser, making it so that Bowser must beat the vacuuming force of the black hole every turn (or at least until phase 2 of the battle starts). After Bowser deals enough damage to the castle, phase 2 begins.The Super Peach Castle tries to make a second black hole, but Bowser shoots a fireball at it, making the black hole go behind the castle instead. After a while, the Castle will activate many defense systems, such as the Boo shield. The castle makes the black holes come closer to the two titans, making it all the more harder for Bowser to attack. Bowser now must depend on counterattacks to defeat the castle, as it puts up a force field, preventing normal damage. If Bowser punches the castle, it gets sucked into the black hole, but retaliates by rocketing towards Bowser, which can be countered with a punch. After a long and hard battle, Bowser successfully demolishes the castle, and moves on to defeat Dark Fawful and Dark Bowser.