Moridin is the name given to Ishamael upon his resurrection. He was given the title Nae'blis by the Dark One—allowing him to command the other Forsaken—as the Dark One felt that the time for individual schemes was over and that the Forsaken should work together to thwart Rand al'Thor. Despite being Nae'blis, Moridin's position is not secure as the other Forsaken frequently conspire to remove or kill him when their plans to not interfere with his. They believe that he is even madder than was as Ishamael, though he has much more control over himself.
As nae'blis, Moridin is theoretically the only person to have access to the True Power, the source of the power drawn directly from the Dark One. However, during the events of A Crown of Swords, he encounters Rand in the ruins of Shadar Logoth, though Rand is unaware that he is one of the Forsaken. Rand, drawing on the One Power and Moridin, drawing on the True Power, both fire balefire. The two bolts of balefire touch, creating a link between Rand and Moridin. The two are now aware of each other and have unconsciously adopted each other's mannerisms. Furthermore, Rand is now able to access the True Power (though again, he is unaware of the exact nature of it), whilst Moridin is susceptible to the taint on saidin. The connection is so strong that in The Gathering Storm, Moridin unknowingly draws Rand into his dreams and his left hand aches after Rand loses his left hand in an encounter with Semhirage. despite his knowledge of the One Power, Moridin is unsure of the nature of the bond and personality aspects that are transferring between them, and he has expressed confusion over feeling Rand's tiredness.
Moridin is present during the final confrontation between Rand and the Dark One. He attempts to kill Alanna Mosvani, an Aes Sedai bonded to Rand, as he knows that severing the link between them will drive Rand into an inconsolable rage. Nynaeve al'Maera uses conventional healing techniques to save Alanna long enough for her to release Rand from his bond, ending the threat. Rand then lets Moridin believe that he has control over Callandor, before he, Nynaeve and Moiraine Damodred seize control from him and use both the One Power and the True Power to shut the Dark One out from the world, closing the Bore. Rand and Moridin swap bodies during this process, though it is not clearly stated Rand intended to do so. Moridin, in Rand's body, dies of his wounds, and the world believes the Dragon Reborn to have died.
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