- Cerberus, the original dog from Hell, and guardian of the dead. He's usually shown as having three heads, but he's occasionally been represented with as few as two and as many as fifty. I'm inclined to think that L. Frank Baum had Cerberus in mind when writing The Emerald City of Oz, which had the Nome King having those who displeased him cut into pieces and fed to seven-headed dogs. And he's obviously the model for Fluffy in the first Harry Potter book, although I think the idea of music to put him to sleep came from other Greek myths, unless there were versions of the Orpheus story in which his lyre lured the canine into a dog-nap. Cerberus allows the spirits of the dead into Hades, but won't let them back out.
- Orthus, the two-headed dog who herded the cattle belonging to the three-bodied giant Geryon.
- The Chimera, a fire-breathing beast that was part goat, part lion, and part serpent. He was killed by Belerephon, riding on Pegasus.
- The Sphinx, a creature with the head and breasts of a woman, the body of a lion, eagle's wings, and a serpent tail. She was based on the Egyptian sphinxes, which were placed outside temples. I don't think any of them had wings, though (if so, it was rare). Of course, lions and eagles are popular components for mixed-up monsters, like the later griffins, and the cherubim of the Bible. The Sphinx had a habit of asking riddles, and then killing anyone who couldn't answer properly. Since Batman wasn't around to solve the riddle, the task instead fell to that literal motherfucker Oedipus.
- The Lernaean Hydra, a monster that I covered back when mythological snakes were the subject of the week. If you ever end up fighting a hydra, remember to cauterize the necks after cutting off the heads, so they won't grow back.
- Ladon, a dragon who guarded the golden apples of the Hesperides by coiling around the tree on which they grew. As with several of these other monsters, it was Hercules who ended his life. I wouldn't be too surprised if this serpent guarding an apple tree was the reason why the forbidden fruit of the Garden of Eden (which grew on a tree that had its own serpent, although he tried to lure people TO the fruit instead of keeping them away) is often identified as apples.
- And finally, the Nemean Lion, whose skin was impenetrable to weapons, but who couldn't prevail against Hercules' bare hands. He wore the lion's skin, which maintained its protective properties, after this. There's actually some debate about the lion's origins, as some versions of the myth claim that he fell from the Moon.
So, let's see. We have two dogs, two weird composite monsters, a snake, a dragon, and a lion, all apparently siblings. But that seems to have often been the way with mythological monsters. I believe Tiamat's offspring included a lot of different sorts of creatures, as did Loki's. I guess monster genetics doesn't exactly work like ours, as anyone who's played Dragon Warrior Monsters would know.