A transformable toy transformable so as to be coupled to a model toy and a toy set including the model toy and the transformable toy are provided. The transformable toy includes a transformable body. The transformable body is configured to be transformable into a first state where the transformable body is independent from the model toy and a second state where the transformable body at least partially covers the model toy and is releasably coupled to the model toy. The transformable body includes a pair of grip portions. The pair of grip portions are configured to be rotatable in opposite directions about one rotation axis or a pair of rotation axes and are configured to releasably grip the model toy by being moved toward each other.