M'hael
Taim is a very power-hungry individual, as evidenced by his claim to be the Dragon Reborn. He is spiteful of those more powerful than he, but is willing to become their underling if in exchange for a position of his choosing. This is what led to his dissension with Rand. He appears at first very willing to be second to Rand, but with a title and power of his own choosing, which Rand is unwilling to allow. Taim first begins to resent Rand when he places him in the farm, from which the Black Tower would spring, to teach men who sought to learn to channel, instead of allowing him to stay by Rand's side. When Rand confers upon him the title of Asha'man, he is clearly unhappy about being seen as second to him. After that day he never wears the black garb of Asha'man, nor the Sword pin of the Dedicated or the Dragon pin of the Asha'man. Instead he calls himself M'hael (in the Old Tongue, something with overtones of "Divine Emperor" or a petty god) meaning leader, and electing garments adorned on the sleeves with Dragons, to make himself seem equal to Rand. The two are at silent war with each other: Rand is unable to kill him despite his treacheries because he is holding the Black Tower together for him to use at Tarmon Gai'don, while Taim cannot risk trying to kill Rand personally because Rand is more powerful than he, and any open action against him could turn Asha'man who are loyal to Rand against him.
There are suspicions that Taim is a darkfriend, in light of his connections with the renegade Asha'man Rochaid and Kisman. They have been shown to defer to him as if he was one of the chosen. There are many such instances littered throughout the series where Taim's intentions are shown to be counterproductive to Rand's.
In Knife of Dreams, Taim met with the White Tower Aes Sedai and agreed to allow the bonding of Asha'man by sisters of the Red Ajah. His justification for this was to "Let the Lord of Chaos rule," a phrase unknown outside the circle of the Forsaken and high-ranking Darkfriends (possible evidence that he may be a Darkfriend or a new Dreadlord). His house is also described as largely decorated with the colors red and black, possible evidence of ties to Moridin, who dresses his servants in the same colors. This link to Moridin is made almost certain by the Dreamspike located at the Black Tower, previously described by Moridin as being "put to good use".
Logain claims that Taim has a small sect of followers whom he personally teaches weaves that no other Asha'man know. Taim refuses to believe that Rand was responsible for the cleansing of saidin. In Towers of Midnight, a group of Asha'man loyal to Logain comes to a frightening realization: Asha'man that take personal lessons from Taim become powerful with unreasonable speed and simultaneously change drastically. Their eyes and smiles become cold and dead, and while they try to pose as former selves, their former companions sense evil. At the same time, one of the Aes Sedai from the delegation suddenly realizes that two members of her group irrationally insist on staying in the Black Tower, after which she notices the same symptoms as those affecting the Asha'man. This and the fact that channelers are unable to make gateways around the Black Tower, while Taim prohibits them to leave the premises without his knowledge, confirms him to be a Darkfriend. This is confirmed by Moridin, who hints that out of the two Dreamspikes he owns, one is placed near the Black Tower and "put to a good use".
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