Riku (Halloween Town)

Riku's Halloween Form is a form of Riku exclusive to Kingdom Hearts Re:Chain of Memories. While it doesn't change Riku's appearance as drastically as Sora, Donald, or Goofy's, it does slightly darken his features. Riku only takes on this form when in the card world Halloween Town.

Kingdom Hearts Re: Chain of Memories
A boy who was born and raised on a small group of islands.

Riku dreamt of seeing other worlds, and so he forsook the islands--only to be seduced by the power of darkness.

Enslaved by Ansem, pursuer of darkness, Riku clashed with his childhood friend Sora.

But in the end, he was able to regain himself, and together with Sora closed the door to darkness.

Still, the dark wounds in Riku's heart have yet to mend.

Appearance
While in Halloween Town, Riku's complection is darkened. His hair and outfit also grow darker, Riku's facial expression more grim, as seen in the D-Report image. While in Dark Mode, these physical changes to Riku's body carries over. The Soul Eater Riku wields is darkened as well, texture lines on Riku's body more exaggerated.

Trivia

 * Riku's Halloween Form is a Re:Chain of Memories exclusive. His form does not change appearance when exploring Halloween Town in the original Chain of Memories.