Maiar - Túvo
Túvo (later called Tû) the wizard was king of the Elves who did not follow Oromë to Valinor. He was known as the Lord of Gloaming, and dwelt in the deep caverns beneath Koivië-néni (Cuiviénen):
"Now the places about Koivië-néni the Waters of Awakening are rugged and full of mighty rocks, and the stream that feeds the water falls therein down a deep cleft [illegible] a pale and a slender thread, but the issue of the dark lake was beneath the earth into many endless caverns falling ever more deeply into the bosom of the world. There was the dwelling of Tû the wizard, and fathomless hollow are those places, but their doors have long been sealed, and none know now the entry."
The Book of Lost Tales, Part One, p. 232, hardback edition
One of Túvo's people, an elf named Nuin, wandered eastward, where Túvo did not send his people. Nuin discovered Men sleeping in a vale full of fragant smells, named Murmenalda, the "Vale of Sleep", and in version D the "Slumberous Vale". He went back and told Túvo, who became fearful of Manwë and Ilúvatar and commanded the Elves to not go to the Vale of Sleep; but Nuin still went back. Later, Nuin woke two Men, Ermon and Elmir, out of curiosity, and taught them speech. Túvo protected Elves and Men from the servants of Melko, but one of them, "Fúkil, Fankil, or Fangli", came and caused some Men to fight against the Elves. After the battle, Men dispersed and met the Gnomes, who sent out embassies, including ones to Túvo and Ermon.
After the Sun first rose, Tû faded, and hid in his deep caverns.
Name: the name Túvo or Tû may be related to the Gnomish name Uduvna for Utumna (Melko's fortress) which is related to Qenya tumna 'deep, profound, dark or hidden', which would be fitting, as Túvo lived in deep caverns; but they may be unrelated.
Addendum-V: Gilfanon's Tale A and B versions both say "that it was after the escape of Melko and the ruin of the Trees that Túvo entered the world and 'set up a wizard kingship in the middle lands'."
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