Arborea (Dungeons & Dragons)

In Dungeons & Dragons, fantasy role-playing game, Arborea or more fully, the Olympian Glades of Arborea, is a chaotic good-aligned plane of existence. It is one of a number of alignment-based Outer Planes that form part of the standard Dungeons & Dragons (D&D) cosmology, used in the Planescape, Greyhawk and some editions of the Forgotten Realms campaign settings.

Arborea is also referred to as "Olympus" or "Arvandor", though technically those names describe separate realms within the plane. Arborea is stylised as a peaceful plane of natural beauty with a multitude of thriving environments. Much of the plane is dominated by vast tall forests, but also includes glades of wildflowers and fields of grain. As a plane that also embodies chaos, it has a wild and often sudden nature. The weather can change drastically at short notice, changing from warm sunshine to raging winds and back again in just a few minutes.

The plane known as Olympus was mentioned for the first time by name in the article "Planes: The Concepts of Spatial, Temporal and Physical Relationships in D&D", in The Dragon #8, released July 1977. The plane was mentioned again in an appendix of the known planes of existence in the original (1st edition) AD&D Players Handbook, published in June 1978, where it was described as "The planes of Olympus of absolute good chaotics".

The eladrin, powerful elf-like celestial creatures are the protectors of Arborea, the most common of which is the Ghaele. Lillends are also common on the plane. Many types of celestial and anarchic version of common animals, natural creatures suffused with tendencies of good or chaos, are found in Arborea. Also, primitive Orc-Baboon hybrids known as Losels dwell in its wilderness, occasionally migrating between it and the Beastlands.

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