Key Points

- Giant Crab killed by Hercules

- Turned into a constellation by Hera 

Brief Bio

Cancer also known as Carcinus is a giant crab in Greek mythology that inhabited the lagoon of Lerna. He is a secondary character in the myth of the twelve labors of Heracles, who attacks Heracles on Hera's orders, while Heracles is in the midst of fighting the Hydra of Lerna. Heracles kills the Crab, who is rewarded for his efforts by Hera turning him into the constellation of Cancer.