Merlin of Amber
Merlin is the narrator and main character in the second half of the Chronicles of Amber by American science fiction author Roger Zelazny. He is an incidental character in the first half of the series, eventually being revealed to be the listener to whom Corwin relates the tale of his attempts to take the throne of Amber, and dealing with the subsequent invasion from Chaos.
Merlin is the son of Prince Corwin of Amber and Lady Dara of Chaos. Raised in the Courts of Chaos, Merlin became interested in his father and Amber after the Patternfall war. In his youth, he studied magic in the Courts of Chaos and walked both the Logrus and the Pattern. After this, Merlin travelled to Shadow Earth to study computer science at the University of California, Berkeley, assuming the name Merle Corey. During his time in college, Merlin made friends with a fellow student Luke Reynard who was, unbeknownst to Merlin, his cousin Rinaldo, son of Brand. Merlin combined his magical and computer skills to create Ghostwheel, a powerful artificial intelligence with the ability to move itself and others through Shadow.
Though Merlin was targeted for many years by an unknown antagonist, he was content to remain on the Shadow Earth. However, he became suspicious when he discovered his ex-girlfriend was murdered by a creature from Shadow, and his investigation was the catalyst for his choice to leave Earth. During the course of his travels through Shadow, he learned the identity of his nameless enemy, as well as that of his friends. With the rapid increase of his powers, the Pattern and the Logrus each attempted to persuade him to ally with Amber or the Courts of Chaos, respectively.
Merlin has a very different personality than his father and, oddly enough considering his upbringing, considers himself to be a "regular guy". He lacks both the ruthlessness and the crudity of Prince Corwin, and seems to be almost allergic to ambition, a rare trait considering his parentage.
Merlin has two half-brothers named Despil and Jurt, sons from Dara and Duke Sawall. Jurt, believing Merlin to be the favorite of their mother, tries several times to kill Merlin; however, he usually ends up leaving some part of himself behind.
As the son of the Chaosian Dara, Merlin was trained in spell-casting, but he frequently relies on the objects he carries with him. Frakir, a piece of rope enchanted during Merlin's walk through the Logrus, warns of danger and acts as a weapon. When the Ghostwheel computer is completed, Merlin occasionally "wears" it in the form of a bracelet. Merlin eventually discovers a ring of great power called a spikard, and abandons Frakir after Frakir objects to the spikard. Merlin also obtains an unusual set of Trumps that contains many locations and individuals absent in a normal deck.
Merlin's other abilities include shape-shifting (a usual talent of the Chaosians) and Trump creation. He also uses the Logrus emanation to reach into Shadow and retrieve various objects, as well as "Logrus sight" which enables him to see patterns of magic and dimensional anomalies. Though he was trained in swordsmanship and other forms of combat, his talents are not found in those areas and he rarely uses purely physical means to fight.
Ghostwheel is a trump- and pattern-based computer constructed by Merlin in a Shadow where Earth physics do not apply. By Merlin's description Ghostwheel's operations involve "a lot of theoretical crap involving space and time and some notions of some guys named Everett and Wheeler". Ghostwheel speaks with Merlin's voice, occasionally causing confusion, and usually takes the appearance of a spinning circle of light. Ghostwheel usually addresses Merlin as "Dad."
After finishing construction, Merlin set Ghostwheel to work indexing Shadows in the same way that a search engine indexes the internet. Similar to a search engine, Ghostwheel can find, track, and retrieve objects from Shadow; this includes the ability to move people and objects between Shadows. Ghostwheel operates by creating pseudo-Trumps for every mutation of Shadow and then searching them.
Merlin designed Ghostwheel as a tool to be used by Random, King of Amber, for keeping watch on Shadow for the protection of Amber. When introduced to Ghostwheel and its abilities, Random was immediately struck by the construct's potentially dangerous power and ordered Merlin to deactivate his creation. However, by this time Ghostwheel had attained sentience and resisted shutdown.
After regaining Ghostwheel's trust, Merlin came to rely heavily on his powerful creation, and Ghostwheel features as a major subcharacter throughout Merlin's saga. By the conclusion of the series, Ghostwheel had developed enough that his support of Merlin forced the Pattern and the Logrus to treat the pair as nominal equals rather than pawns.
At one point, Ghostwheel asks Merlin whether it is a god. In the consideration of sentient machines with godlike resources for accessing and processing information, this draws interesting parallels to Isaac Asimov's short story The Last Question.
Merlin also remarks that Ghostwheel is certainly capable of passing the Turing Test, which is a test for a machine that can demonstrate the ability to convince an observer of a human-like personality.
Ghostwheel seems to take its name from Gilgal Refaim or Rujm el-Hiri, an ancient stone circle in the Golan Heights. Gilgal Refaim may have once been a pagan place of worship or calendar, similar to Stonehenge.
The name Merlin refers to Merlin, the character from Arthurian legends. Both were sorcerers who were imprisoned in a crystal cave, although the circumstances were somewhat different.