Darkover is/was based on the novels and short stories written by Marion Zimmer Bradley et al. http://darkover.apiacoa.org/index.en.html

Darkover was run by Clarissa, an ancient, powerful, and devious sorceress. Darkover was the center of the Matrix, a blue crystal power of Life Magic.

During the course of the game run Darkover was razed by a suicide force from Chaos. Princess Chandra and Pharaban were the two survivors of that strike; Imagio of the Psionicists and Bella were two notable fatalities. During the strike, Clarissa called upon all the power she had at her disposal, including all the Grey Spheres available to her, and the life-force of all of her descendants she could reach. Amongst those used up by her in this combat were Fiona, Bleys, Brand, Celeste, Rhiannon, Desilira, Charynna, Valdyn, Roberto, and Alicyna. After the suicide force’s strike succeeded Clarissa was unmade by Shiryu for the good of the Garden.

Darkover is now run by Faythe, and the Saviour of Chaos has imported a few cities to repopulate it. Just prior to the Shadow Purge, Ilk brought over the entire crust and atmosphere (intact) from the planet where the Count of Cagliostro lived. The crust was spread out over a (hopefully) unpopulated area of Darkover, and a twelve-mile ramp was constructed to desert level.

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The Sea of Thought, mostly but not entirely composed of members of the Philosophers Guild, has also been migrated to Darkover. It sits near the base of the ramp connecting the crust to the desert.

Serpent’s Apprentice brought a city controlled by Samantha to Darkover, and she has continued to manage it there. The city was higher technology than the rest of Darkover, and after its migration was known as “Terra Port” (at least by Faythe).

Osric towed the entire promontory across the Sea of Chance to be much more proximate to Chaos just post the Shadow Purge.