Tetrahedron 1

A tetrahedron 1 may be found in a secret compartment on the 1st floor of the accessible part of Kethsi.

Continuing along the relation that Kethsi may have ties to the dragonkin, the tetrahedron closely resembles the four corners of the dragonkin's compass rose symbol. This is also supported by the fact that there are 4 tetrahedon.