What would the heroes be without something to kill or capture? These guys were not only nasty, they did bad things too.

Name Residence Killed By
Nemean Lion Nemea Herakles
Hydra Lerna Herakles
Cerberus Gates of the Underworld ?
Sphinx Thebes Oedipus
Chimera Lydia Bellerophon
Ladon Hesperia Herakles (or Atlas)
Draco ? ?
Medusa ? Perseus
Stheno ? ?
Euryale ? ?
Cetus Ethiopia Perseus
Griffins Near Boreas' Cave ?
Harpies ? ?
Asterion (the Minotaur) Labyrinth of Crete Theseus
Scylla Strait of Messina ?
Charybdis Strait of Mesina ?
Caledonian Boar Caledonia Meleager
Sirens An Island ?
Typhon Mt. Etna ?
Echidna A Deep Cavern Argus
Orthos Erythia Herakles
Aquila (the Eagle) Caucasus Herakles
Unicorn ? ?
Chryasor Gorgons' Cave ?
Delphyne Korykian Cave (in Kilikia) ?
Geryon Erythia ?