I wonder, since DY wasn't always known by that name, Toland has extensive disturbing knowledge of the darkness and hive magic (like was used in thorn) And nobody knows what happened to him.
It's a Hail Mary, but I'm not sure there is evidence to the contrary.
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Notice the similarity between the name yor and xyor? Xyor is who you fight for the thorn bounty. DY became corrupted by the thorn making me believe he turned into xyor