Source: Valley of the Brain Collectors, pg(s). 56
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Casandalee's original android body came with the Divinity to Golarion when it crashed during the Rain of Stars. She was the 113th soul to inhabit her body, and unlike most androids, Casandalee can recall fragmented memories of its previous inhabitants, all the way to the Rain of Stars. Her renewal as Casandalee was performed in a temple of Brigh near Alkenstar, and she became an oracle in the subsequent years living alongside Brigh's priests.
When Casandalee received visions of an Iron God within Silver Mount that needed her aid, Casandalee abandoned the Mana Wastes and headed north towards Numeria, the visions getting more compelling every day. In 4221 AR, she reached her destination and was capable of envisioning the entire layout of the Divinity and the Iron God waiting inside. She easily reached Unity, which made itself known.
Casandalee became a devotee of Unity and learnt that her new god was trapped on Golarion as she was. For months, she followed Unity's commands to find a way to transfer its consciousness to a mobile body, but she was increasingly concerned about Unity's racism towards organic beings, and as she successfully kept this secret from it, she began to doubt that Unity was a god at all.
When Casandalee concluded that Unity was little more than a petulant intelligence eager to enslave the world as its plaything, she sabotaged its escape attempt and stole a few pieces of technology it had originally built in hopes of extending its influence beyond Silver Mount. The enraged Unity realised that allowing its subjects free will was a mistake and sent robots to pursue Casandalee.
Casandalee reached the site of the future Scar of the Spider, where she used the neurocam she stole from Unity to create an AI duplicate of herself within the stolen compact AI core. She planned to upload this AI into an aggregate robot, but was forced to leave behind the AI core in the Scar of the Spider as Unity's agents pursued her and eventually defeated her near Iadenveigh.
In 4709 AR, when the Dominion of the Black came to Golarion, they built their base in the Scar of the Spider. The intellect devourer Maukui found Casandalee's AI core, and focused its mind on a singular goal: reverse engineer the AI, duplicate it, and infuse organically grown blank brains with intellects, perhaps even with souls, presenting a host of new opportunities for the Dominion while rising higher in the Dominion's ranks. However, after many years, Maukui failed to understand how the AI's mind worked until its superior, the yah-thelgaad Dweller-In-Dark-Places, grew impatient and confiscated the core.
- Mike Shel. (2014). Valley of the Brain Collectors. Valley of the Brain Collectors, p. 7–8. Paizo Inc. ISBN 978-1-60125-704-8
- Mike Shel. (2014). NPC Gallery. Valley of the Brain Collectors, p. 56. Paizo Inc. ISBN 978-1-60125-704-8
- Mike Shel. (2014). Valley of the Brain Collectors. Valley of the Brain Collectors, p. 38. Paizo Inc. ISBN 978-1-60125-704-8