Combined four-color transit light curves of HATS-2 obtained with the GROND imaging system. Green dots are for the data taken in the g band, yellow upside-down triangles for the r band, red squares for the i band, and purple triangles for the z band. Top panel: transit observed on February 28, 2012. The bump observed just after the midtransit is interpreted as the covering of a “cold” starspot by the planet. Lower panel: transit observed on June 1, 2012. In addition to the bump occurred near the egress part of the light curve, a “hot” spot manifested in the g band, just before the start of the covering of the starspot.