Eurystheus's Assassination of Hercules

Hercules took his bow and arrows, and in the forest of Nemia cut himself a great club. This club he carried ever afterwards as his chief weapon. He found that his arrows had no effect on the tough skin of the lion. The next task given to Hercules by Eurystheus was to destroy a huge water snake called the hydra which lived in the marshes of Argos. From the stump of each head that he cut off, two other hands with forked and hissing tongues immediately sprang. It seemed to him that he might prove more powerful than cold steel.