There is currently a bug (Version 1.1) that causes some of the wallpapers to be treated as another item in several cases. The light green wallpaper (pictured below) corresponds with the Prismatic Shard, and can be used as a universally loved gift (except when given to Haley) and to acquire a Galaxy Sword at the Three Pillars in Calico desert.
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There is currently a bug (Version 1.1) that causes some of the wallpapers to be treated as another item in several cases. The light green wallpaper (pictured below) corresponds with the Prismatic Shard, and can be used as a universally loved gift (except when given to Haley) and to acquire a Galaxy Sword at the Three Pillars in Calico desert (not giftable in beta version 1.2.13, still usable to receive Galaxy Sword).