|Book(s)||A Feast for Crows (appears)|
The alchemist is a young man with a hooked nose and thick, black, curly hair. He has the shadow of a beard and there is a faint scar on his right cheek. This is an identical description to the appearance assumed by the Faceless Man assassin known to Arya Stark as Jaqen H'ghar during the fall of Harrenhal.
A Feast for Crows
The serving wench Rosey of the Quill and Tankard inn introduces the novice Pate to a hooded stranger, who dances a gold dragon coin over his knuckles and says he will exchange the gold for the iron key of Archmaester Walgrave, whom Pate serves. Desiring the coin so he can buy Rosey's maidenhood, Pate is given three days to consider.
Three days later, Pate is at the Quill and Tankard with the key he stole from Walgrave's strongbox. Pate completes his transaction with the alchemist in a narrow alley. He is hesitant, because an archmaester's key is supposed to be capable of opening any door in the Citadel, such as to locked vaults containing rare Valyrian scrolls. Pate bites the coin as he has seen others do. When the alchemist reveals his face, Pate does not recognize the young man. Pate gives the alchemist the key and leaves, but his legs go weak and his heart starts hammering, he falls and dies.
When Samwell Tarly meets Archmaester Marwyn at the Citadel, a novice with the same features as the late Pate is present in his chambers. He identifies Marwyn's glass candle as obsidian, and listens as Sam tells his story. When Marwyn leaves for Slaver's Bay, he commands Sam to stay and forge a maester's chain and help with the ravens. The novice tells Sam that there is an empty sleeping cell under his own in the west tower of the Ravenry, with steps that lead to Archmaester Walgrave's chambers. Sam thinks there is something about the pale, soft youth that he dislikes, and the novice introduces himself as Pate, "like the pig boy."
Pate: I do not know you.
Alchemist: Nor I you.Alchemist: A stranger. No one. Truly.
Pate: Who are you?
—Pate and the alchemist