This is a giant polymer clay egg which i am documenting as I go, as a process which needs to be refined (LOL) and may not be a realistic expectation for any sculpture with polymer clay.
It is clear that polymer clay is both heavy and expensive, and that armature is a good idea, and also that when it is cured it can bend, bulge, shrink and otherwise distort so there needs to be some kind of support for large structures.
I have tried to second guess this medium, having seen first hand that there are some areas where it is easy to “fail” but maybe not enough.