Well World series

The Well World series is a series of science fiction novels by Jack L. Chalker. It involves a planet-sized supercomputer known as the Well of Souls that builds our reality on top of an underlying one of greater complexity but smaller size. The computer was built by a now-extinct race, the Markovians, who developed the Well of Souls with the goal of creating a new species that would transcend their own.

The Well World is the planet that houses the Well of Souls, and it exists within the original Markovian reality. Its surface was used as an experimental site where the Markovians tested their species designs before sending the successful ones into the new universe to populate planets. Humans are one of many such designed species who now live in the "real" world. During the time period of the novels, the Well World has been abandoned and left on its own for an unknown length of time.

The books mainly follow a mysterious character known as Nathan Brazil, who has an (initially) unknown connection to the Well World. The books are adventures that follow Brazil and a changing cast of secondary characters through a series of visits to the Well World over a period of hundreds (and millions) of years.

The series is largely set on a fictional planet named Well World. The Well World was constructed by an ancient alien species, known as the Markovians, who felt they had reached a dead end in their evolution. The Well World houses a planet-sized, reality-shaping computer that creates an artificial universe layered on top of the much smaller, original Markovian one. The Well World exists within the original Markovian universe, and can only be accessed through gateways on a number of Markovian planets scattered through the artificial universe. The Markovians experimented in species design on the Well World, sending the more successful ones into the new universe to populate one of these planets. By the time of the stories in the series, the Markovians have vanished, leaving behind the Well World, continually maintaining the new universe.

The Well World's surface is composed primarily of 1560 large hexagonal regions — called "hexes" — each with an independent and often dramatically different climate and ecosystem, that David Langford compares to the hexagonally tiled boards used in "hex-and-counter" forms of tabletop wargaming. Each of these hexes is a prototype environment for a planet that exists in the external universe, half of which, comprising the planet's southern hemisphere, contain carbon-based (or similar) oxygen-breathing life. The North is made up of exotic species which are often so alien that no common ground exists between them and the Southern races, and, often, their Northern neighbors as well. Since the Northern hemisphere contains, for example, seas of oxygen, chlorine, methane, and ammonia, Southern races need some kind of life support in the North. The two hemispheres are separated by an impermeable wall that extends "several kilometers upward." In the hexes that are bisected by the wall there is a separate gateway (the "avenue") to the Well of Souls, the control center for the computer.

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