Create a 3D rig of an anthropomorphic frog that is both muscular and plump, similar to a pink hippopotamus. The character should have humanoid features with webbed fingers and toes, smooth skin, and large, expressive eyes. Ensure the rig includes fully articulated limbs, a flexible spine, and detailed facial expressions. The frog should have a strong, powerful physique with prominent muscles and a robust body, highlighting its natural wet skin texture.