Arachne
It has also been suggested that Jeremias Gotthelf's nineteenth century novella, "The Black Spider", was heavily influenced by the Arachne story from Ovid's "Metamorphoses". In the novella, a woman is turned into a venomous spider having reneged on a deal with the devil.
Lernaean Hydra
The alternate version of this myth is that after cutting off one head he then dipped his sword in its neck and used its venom to burn each head so it could not grow back. Hera, upset that Heracles had slain the beast she raised to kill him, placed it in the dark blue vault of the sky as the constellation Hydra. She then turned the crab into the constellation Cancer.