Divinity: Original Sin 2 - Definitive Edition (UP)

This is located in Act 2 on bloodmoon island (top left of the map) depending on the difficulty; I play on classic; and completed this at level 15 without much of a struggle.

To start you must have at least 22(?) Wits and a method to dig with. (Shovel or lizard character). If your lacking wits try using the pyro skill "peace of mind" for an extra 4.

Once your on bloodmoon island your going to want to follow the edge of the island counter-clockwise until you reach X:366 Y:466. Once there; if you meet the requirements a dig spot will be revealed to you, once you dig up the hatch continue down into the Archives. There are no enemies down there to worry about, but you need to search all the book piles for "Archivist's Journal" and read it to gain the name of the tree in the center of the island.

Next; (if you haven't all ready) your going to have to fight the Black Rings surrounding the tree. This fight isnt particularly hard. You must kill the advocate to talk to the tree. Once he is dead, use Spirit vision and talk to the tree, until you see the dialog to tell him his name.

If you have a character with the "mystic" trait I dont believe you need the Archivist's Journal.