A reccurring boss in Super Mario Bros. Wonder. Bowser Jr. juiced up in Wonder Power.
His yellow skin becomes blue, his green shell becomes purple with green spikes, his red hair becomes green flames, and his mouth fuses with his bandanna to become a massive snapping jaw that is almost reminiscent of a bear trap. His eyes also becomes glowing pink/white and he becomes covered in Sparkles.
The design reappears in The Super Mario Galaxy Movie after Bowser Jr covers himself with goop from his magic brush. An advanced alternate form also appears, with a color scheme similar to Fury Bowser.