Hydra monster
The Lernaean Hydra or Hydra of Lerna (Greek: Λερναῖα Ὕδρα, Lernaîa Hýdra), more often known simply as the Hydra, is a serpentine water monster in Greek and Roman mythology. Its lair was the lake of Lerna in the Argolid, which was also the site of the myth of the Danaïdes.