Sauron

Sauron /ˈsaÊŠrÉ’n/[1] is the title character[note 1] and main antagonist[3] of J. R. R. Tolkien's The Lord of the Rings.

In the same work, he is identified as the Necromancer, mentioned in Tolkien's earlier novel The Hobbit. In Tolkien's The Silmarillion (published posthumously by Tolkien's son Christopher Tolkien),[4] he is also described as the chief lieutenant of the first Dark Lord, Morgoth. Tolkien noted that the Ainur, the "angelic" powers of his constructed myth, "were capable of many degrees of error and failing", but by far the worst was "the absolute Satanic rebellion and evil of Morgoth and his satellite Sauron".[5]

https://en.wikipedia.org/wiki/Sauron