Windseer Grayhorn in Conquest Hold wants you to go to Vordrassil's Heart, Vordrassil's Tears and Vordrassil's Limb and use the Geomancer's Orb in the depths beneath the surface.
1x Orb used beneath Vordrassil's Heart.
1x Orb used beneath Vordrassil's Limb.
1x Orb used beneath Vordrassil's Tears.
Something... dark... happened to the tree Vordrassil. After the druids decided to destroy it, its hollow remains grew roots deep into the ground.
I want you to go to the three locations to the northeast where the tree's trunk shattered and go as far beneath the ground as you can.
Use this orb once you get there to get an imprint of the energy surrounding the area. This might shed some light on what happened to Vordrassil and why it failed to become a world tree.