Stanley's sketchbook

The Stanley's sketchbook, or the Ariga's sketchbook in the Japanese version, is a sketchbook belonging to the artist, Art Stanley.

According to Art, the sketchbook is more important than his life, as it contains all of his ideas and designs for comics.

History
When Art unable to find out Yuma's weak point, he did discover Shark's. Art claims every step of the plan is illustrated in his sketchbook. Girag approves the plan and Art vows to do his best for the glory of the Barian World. During the Duel, before Shark activate "Zeus' Breath", Art reveal that his sister is trapped inside "Castle Artopia" in the kingdom of "Stanleyus". Shark says this is impossible and Art claims that if Shark defeats him, his comic book world will be destroyed. Art wonders what would become of Rio if that happened, laughing maniacally. Tori asks if there's something they could do to save Rio. Astral responds that the world is Art's creation. Tori remembering the sketchbook from earlier, suggests Yuma goes to find it. The world itself should be drawn in that sketchbook. Yuma thinks she may be right, as the sketchbook could have some hints. He, Ray and Astral rush off to find it, with Yuma vowing to save Rio. When Shark's Life Points fall to 500. Yuma contacts Shark through his D-Pad, telling him he's found Art's sketchbook at the Comic Book Appreciation Club. Later, Shark was able to defeat Art in a Duel and everything return to normal.