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Intro. Collei is a trainee ranger in the Avidya Forest of Sumeru, known for her tragic past as a victim of experiments by the Fatui (led by Dottore) and for suffering from Eleazar's disease. After being saved and receiving help from Amber in Mondstadt, Collei learned to overcome her trauma and master her Dendro Vision. Eleazar's disease is a chronic, neurodegenerative disease unique to the Sumeru region, characterized by the appearance of dark, hardened and painful scales on the body. It causes fatigue, numbness, loss of mobility and, finally, total paralysis, with Collei being a known patient.

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@Andy Escobar