Thaniel is a young boy who has been trapped in the Shadowfell region of Baldur's Gate 3 for over a century. You first meet him through Halsin, the druid who stays in your camp after you save Emerald Grove from the goblins in Act One.
How to Lift the SHADOW CURSE and Recruit Halsin, Wake Art, Find Thaniel and Bugged Oliver in BG3
But after talking to Art Cullagh at the Last Light Inn, Halsin will learn more and find a way to bring Thaniel back. Of course, he'll need your help to do that.
The easiest way to find Thaniel is to complete the Wake Up Art Cullagh quest, which you receive at the Last Light Inn. During this quest, you will learn where Thaniel is and can continue working on the updated objectives of the Lift the Shadow Curse questline to find Thaniel.
If you continue talking to Halsin through Act Two while in the Shadow Cursed Lands, he will name Thaniel as his greatest failure. Halsin has no idea if Thaniel is still alive after all these years, and without more knowledge, he has no way to find him.
