The deeds of Hercules were endlessly popular in the Renaissance as models of strength and virtue. Heinrich Aldegrever portrays the hero engaged in two particularly desperate labors. In one he had to crush the menacing nine-headed Hydra-difficult to do because each time a head was cut off, two appeared in its place. The other task was to descend to Hades and bring back Cerberus, the hideous beast guarding the entrance to the underworld.