Logrus

In The Chronicles of Amber, a series of fantasy novels by Roger Zelazny, the Logrus is a shifting, three-dimensional maze which represents the forces of Chaos in the multiverse.

In the Courts of Chaos exists the Logrus, a three dimensional construct that is the opposite number to the Pattern of Amber. Where the unchanging, rigid Pattern represents Order, the Logrus is constantly altering its shape and represents the principle of Chaos.

The Logrus appears as a tentacular force that must be navigated on a magical/mental level. Those who navigate this construct successfully gain power over, and the ability to travel through, Shadow. An additional power gained from the successful navigation of the Logrus is the ability to "pull" desired, non-specific objects out of Shadow worlds.

Negotiating the Logrus is extremely difficult and potentially fatal. Prospective initiates of the Logrus generally receive advanced training, but success is dependent less on knowledge than on will. In addition to the danger of dying, some who have attempted the Logrus have experienced permanent cerebral damage, though this fate tends to happen only to those who are weak willed or not of full chaosian blood. Luckily those of chaosian blood usually only end up being insane for a short period of time. Negotiating both the Logrus and the Pattern, as Merlin has, is a uniquely daring feat.

Just as Dworkin Barimen is keeper of the Pattern, Suhuy is the keeper of the Logrus and is a member of the noble houses of Chaos.

The Logrus has been called a source of "tactical nuclear weaponry, remote handling and magical apportation".

In one analysis, the Logrus has been construed as a rival metaphysical entity to the Unicorn of Amber, not the Pattern, with the climax of the Merlin Cycle a conflict between these forces.

In Pro Perl, Peter Wainwright makes a punning reference to the Logrus (and the Pattern) in an example of regular expression usage. In the example, a search-and-replace operation is being executed. The text to search for is specified as a regular expression pattern. The sample text to replace the pattern with is logrus.

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