Nightmare of Ka'nok, Failed Assassin
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Nightmare of Ka'nok, Failed Assassin is an Elite Cabal Legionary who can be found in the Dungeon, Duality. They guard the third and final Standard which is required to access the Heartshadow Exotic Catalyst. [1] The name implies they were one of the many assassins who would try to take Emperor Calus's life prior to his ascendancy to one of the Disciples of the Witness.