After [[Mira Tsukumo|Mirai Tsukumo]] gave the key to [[YumaTsukumo (manga)|Yuma]], he had dreams about it for years. The Door says that the one who opens this door will receive great power, but as compensation will lose something important to them. <ref name="ch01">{{chapter|Yu-Gi-Oh! ZEXAL|1|ref}}</ref> During his [[Duel ]] with [[Ryoga Kamishiro (manga)|Shark]], Yuma finally opened the door, leading him to release the "[[Numbers]]" and meet [[Astral (manga)|Astral]].<ref name="ch01ch02">{{chapter|Yu-Gi-Oh! ZEXAL|12|ref}}</ref>