Rolls as a d2 or a d4 or a d6 or a d8 with an easily readable result.
This die is based on the shape Pentagonal Icositetrahedron, which is a Catalan Solid without parallel faces. When the die lands, a vertex will be straight up with three faces around it. Each face will give a result for a different die. The pips around the upfacing vertex will give a d6 result.
In order to use this die, first decide which one die roll you need (d2 or d4 or d6 or d8). Then roll the die and read the result as follows:
Since this shape is isohedral, this should be a fair die.
Photos coming soon (I've ordered this and am waiting for it to arrive).
For a simpler version of this die which omits the d6 numbering (and uses pips for the d4 faces instead of Roman Numerals), see Multi-Die d2/4/8 (Gyroid) v1
For a d24 version of a Pentagonal Icositetrahedron shaped die, please check out ppoz's D24 Pentagonal Icositetrahedron