Gaunter O'Dimm

Gaunter O'Dim sometimes called Master Mirror or Man of Glass, was once merchant of mirrors (at least so he present himself) but now he is a mangy vagrant. He is in several comics most notably comic book named house of glass, He is a secretly a doppler formely serving under the banner of "House of Stone".

The Witcher 3: Wild Hunt
During quest Lilac and Gooseberries, you find him in White Orchard's Inn, he knows about Geralt of Rivia and Yennefer of Vengerberg from Mister Dandelion's ballads and advise you to go to Nilfgaardian garrison near by. Than he sudenly disapear.

Heart of Stone Expanssion
He is a major character and mysterious contractor that hires Geralt in the upcoming Heart of Stone expansion for The Witcher 3: Wild Hunt.Hombre de cristal