Only distinguished, well-drawn, nicely-shaped feet.
None of the typically fucked up pinky toes or mangled toenails. No swollen and unrealistically cushioned soles. No toes that are shaped like fingers. No poor shading when used to define the foot's contour.
No impossible anatomy or contortions. No deformities. No errors.
Note: In the case of parent-child uploads, only the parent should be added to the pool.