This is a self-standing (outer-curved) lithophane of Cell in his Perfect form. It is shown and best printed in GREEN PLA (shown AmazonBasics GREEN).
This object was created using 3DP Rocks Lithophane Builder with the Outer Curve model.
Picture shown is printed on a Creality Ender-3 sliced with Cura, using the Fausto Ender 3 (Normal) Profile, from the Creality Ender User Group Profiles
NOTE: The photo shown is actually not the best quality image. For a better view, Watch the Build to see the lithophane in its "normal" state and when backlit (wait for it).