Ancestral Domain

The  is a Dungeon, released with the 1.17 update.

Location
[-9,-14]

Access
To enter, talk to the Npc Josette Moresyca. You must have a Treechnid Dungeon Key with you to enter.

Rooms
After completing the third room you are being transformed into a Treechnid. So you do not have access to your own spells and have to use spells of the treechnids instead. The mobs you have to fight after the transformation are easy, but not if you are a treechnid yourself.

Room 1

 * Treechnid
 * Red Spimush
 * Green Spimush

Room 2

 * Treechnid
 * Treechnid
 * Trunknid
 * Trunknid

Room 3
Talk to the npc in the room and turn into a tree to get to room 4.

Room 4

 * Treechnid
 * Treechnid
 * Arachnotron

Room 5
?

Follow the red line and You'll get to the other side of map. Then stand in front of the treechnid NPC and talk to it. (you MUST stand in front of it or you can not progress)

Room 6

 * Arachnotron
 * Arachnotron
 * Arachnotron
 * Venerable Treechnid
 * Venerable Treechnid