This is a replacement Heroscape Rock Outcrop (3 Hex) tile from the Battle for the Underdark Master Set.
It was created using a Rock Outcrop sourced from Heroscapers Index of 3D Printed Stl Files and reworked in Tinkercad.
I recommend printing 2 copies of this outcrop if you're interested in recreating tournament maps such as the ones used in GenCon, but only one is required to complete the Battle for the Underdark set.
This print takes about 8 hours, so it's a good overnight. I cut out a cone beneath the print to reduce material used and reduce print time, but it still doesn't require any supports.