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The Source Hunters The Thunder discover that the cult has been mining a highly toxic metal named "tenebrium" in the Luculla Mines, where they also encounter "Death Knights", indestructible undead warriors created by Leandra using tenebrium and the Source to conquer Rivellon. Icara reveals to them that the Conduit is actually her own estranged sister Leandra and directs them to infiltrate the Immaculates to learn of her plans.
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Upon being freed, she introduces herself as Icara and pleads guilty of accidentally killing the councilor, but the Source Hunters, having uncovered evidence of Sourcery, mass murder, and human sacrifice carried out by the Immaculates, choose to ally themselves with her against the common foe. Their search for her takes them to the fairy realm of Hiberheim, where they find her trapped in a block of ice by the Immaculates' leader, the Conduit. They also find evidence implicating the White Witch, guardian of the Luculla Forest, in the murder. Upon arrival, they find Cyseal under siege by orcs and undead and soon discover that it was orchestrated by a Sourcerer conspiracy linked to the Immaculates, a cult based in the Luculla Forest further inland. At the start of the game, the Source Hunters receive orders to investigate the murder of a town councilor by a suspected Sourcerer in Cyseal, a port town in southern Rivellon.
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In the single player mode, the player controls them both, while in the two-player co-op, each players takes control over one of them. The customizable protagonists of the game are a pair of "Source Hunters": members of an organization dedicated to eradicating a dangerous type of magic known as "Source" and its adepts. The game touts turn-based action and adventure, cooperative multiplayer, an interactive world, and includes a modding tool used for creating new content. Divinity: Original Sin concerns two heroes. Original Sin is an RPG in the Divinity universe.
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