I am going to defeat them, Taim. All of them. They think they can tear everything down. It's always tearing down, never building up! I'm going to build something, leave something behind. Whatever happens, I will do that! I'll defeat the Dark One. And cleanse saidin, so men don't have to fear going mad, and the world doesn't have to fear men channeling. I'll...
— Rand to Mazrim Taim
The highest military rank of the Asha'man, the M'Hael holds the supreme rank of Leader, second only to the Dragon Reborn in the Asha'man organization. M'Hael means "leader" in the Old Tongue.
The only M'Hael was Mazrim Taim, who created the position and title himself, acting on his own outside of Rand's command. M'Hael is also the name given to Mazrim Taim as one of the Forsaken.
With the open revelation of Mazrim Taim as a Darkfriend and Forsaken, as well as his defeat during the Last Battle, the future of the title and Black Tower leadership is unclear, especially with the believed death of the Dragon Reborn. Logain commanded the Asha'man loyal to the Light during the Last Battle and, like Taim, is a former False Dragon who began channeling long before the Black Tower was founded. Therefore, it is probable that Logain will lead the Asha'man following the conclusion of the Last Battle. However, whether he will use the title of M'Hael - or even whether he will lead the Black Tower as a sole leader - is uncertain.