Dreamy Bowser

Dreamy Bowser is the result of when Bowser inhaled the shattered remains of the Dream Stone and is the final boss of Mario & Luigi: Dream Team. While in this form, Bowser is in technicolor, is much larger, and has Dream Stone looking objects on his head and stomach.

Mario & Luigi: Dream Team
After Starlow and Peach destroy the Dream Stone, Bowser inhales the broken pieces of it and transforms into Dreamy Bowser. He then engages Mario and Luigi in a battle which, once it results in Mario and Luigi's victory, he transforms back into Bowser and is knocked out of his own castle with the brothers' hammers.