Before you could see Adamantine from the horizon in both the Glenumbra and Stormhaven maps, specifically in the areas around Hag Fen and Koeglin Village.
This picture is taken from near Alcaire Dolmen before when the tower was still visible:
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and these are all from the most recent patch where the tower is missing:
Alcaire Dolmen -
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Hag Fen -
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I'm pretty sure unless the theory of the tower being a spaceship is true, the tower shouldn't leave Nirn
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EDIT: It is back! Thank you for fixing this, my Direnni characters thank you
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Edited by Lady_Sleepless on September 28, 2021 11:34PM