The Wizard's Rainbow – also known as the Bends o' the Bow and Maerlyn's Rainbow – are a collection of thirteen glass spheres with supernatural properties.
The spheres represent the Twelve Guardians of the Beams and the Dark Tower itself.
The Bends[]
The Crimson Bend[]
The Orange Bend[]
Prior to the fall of Gilead, the Orange Bend was in the possession of the Crimson King.
The Orange was later rumored to be in Dis.
The Yellow Bend[]
Prior to the fall of Gilead, the Yellow Bend was in the possession of the Crimson King.
The Pink Bend[]
Also called Maerlyn's Grapefruit, the Pink Bend was once in the possession of John Farson, who left it with the witch Rhea of the Cöos in Mejis. When Roland Deschain and his friends were sent to Hambry, Roland managed to take it and returned it to Gilead, giving it to his father. It was later stolen again after the death of Gabrielle Deschain.
Roland and his new ka-tet encountered the Pink Bend once more at the Palace of Emerald City in Topeka, Kansas.
It brings the power to see long distances the people the owner knows and see the deepest secrets and inmoral things that those people does. For example, Rhea saw Susan and Roland having sex together, and other many secrets of the people of Mejis. Always embarrassing and dangerous secrets.
The Dark Blue Bend[]
The Blue Bend was last seen in the possession of a band of slow mutants who called themselves the "Total Hogs," though they are said to have lost it.
The Dark Green Bend[]
The Green Bend was rumored to be in Lud. If that is the case, it is likely still there following Blaine the Mono's genocide.
The Indigo Bend[]
Prior to the fall of Gilead, the Indigo Bend was in the possession of the Crimson King.
The Lime Bend[]
Prior to the fall of Gilead, the Lime Bend was in the possession of the Crimson King.
The Azure Bend[]
Prior to the fall of Gilead, the Azure Bend was in the possession of the Crimson King.
The Violet Bend[]
The Brown Bend[]
The Pearl Grey Bend[]
The Black Bend[]
Also called Black Thirteen, the Black Bend was once in the possession of Marten Broadcloak, who gave it to Donald Callahan at the way-station in the Mohaine Desert after Callahan crossed over into All-world. Callahan was thereby transported to Calla Bryn Sturgis, where he later met Roland and his ka-tet, offering to trade Black 13 in exchange for their aid against the marauding Wolves.
Mia stole the Black Bend after the showdown with the Wolves and used it and Susannah Holmes' body to escape to New York City of 1999, where she planned to give birth to Mordred Deschain. Jake Chambers and Pére Callahan followed and retrieved Black Thirteen, storing it in a long-term locker beneath the World Trade Center.
If the glass was not destroyed on 11 September 2001, it was almost certainly irretrievably buried beneath the rubble of the collapsed buildings.