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Ulan-Tan was a controversial Warlock whose teachings formed the core doctrine of the Guardian faction known as the Symmetry. Ulan-Tan's Thesis concerning the nature of the Darkness posits that the Darkness is a necessary symmetry to the Traveler in the cosmic balance. As the Traveler's inherent goodness led it to sacrifice itself to stop the Darkness and save humanity, so must humanity return that goodness by healing the Traveler. He also theorized that all Light is interconnected across space and time; Ikora Rey believed this theory was supported by the Hive's use of a shard of the Traveler to remotely leech its Light. For unknown reasons, Ulan-Tan was viewed by the Vanguard as a troublemaker with dangerous ideas that inspired too much fear. At some point, Ulan-Tan died and was interred with a legendary burial ring.
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