He was killed in the Downfall of Númenor, but again took form in Mordor. He was again defeated by the "Last Alliance of Elves and Men". Later in the Third Age, Sauron again came to life, searching for the Ring, and starting the "War of the Ring". Sauron was later defeated when the One Ring fell to the fires of Mount Doom with Gollum. Sauron is mentioned as the Necromancer in "The Hobbit".