Prints flat, around 10 minutes, and then folds to a little pyramid.
Uses only about 2 grams/60 cm of material.
Both PLA and PETG can be used. In the pictures, the blue one is in PLA 0.4 nozzle, the black is in PETG with a 0.4 nozzle, and the red is PETG with a 0.6 nozzle.
FreeCAD design file included if anyone want to tinker more with the design.
The author marked this model as their own original creation.