This corrupted king is the most black-hearted of the fiends. Once, his spirit looked deep within the earth, and he then knew the truth of the Nameless Things. He corresponded with the Balrog Lord, but never told Sauron of this. Sauron divined the truth from his mind, and from then he was, save Ren, lowest of the Nine.
Akhorahil descended into the void from whence he came. He almost enjoyed it.