Cacus
In Roman mythology, Cacus (, derived from κακός, meaning bad) was a fire-breathing giant and the son of Vulcan (Plutarch called him son of Hephaestus). He was killed by Hercules after terrorizing the Aventine Hill before the founding of Rome. Mythology. Cacus lived in a cave in Italy on the future site of Rome. To the horror of nearby inhabitants, Cacus lived on human flesh and would nail the heads of victims to the doors of his cave. He was eventually overcome by Hercules. According to Solinus, Cacus lived in a place called Salinae, which later became the location  of the Porta Trigemina. According to Evander, Hercules stopped to pasture the cattle he had stolen from Geryon near Cacus' lair. As Hercules slept, the monster took a liking to the cattle and slyly stole eight of them – four bulls and four cows – by dragging them by their tails, so as to leave a trail in the wrong direction. When Hercules awoke and made to leave, the remaining herd made plaintive noises towards the cave, and a single cow lowed in reply. Angered, Hercules stormed towards the cave. A terrified Cacus blocked the entrance with a vast, immoveable boulder (though  some incarnations have Hercules himself block the entrance) forcing Hercules to tear at the top of the mountain to reach his adversary. Cacus attacked Hercules by spewing fire and smoke, while Hercules responded with tree branches and rocks the size of millstones. Eventually losing patience, Hercules leapt into the cave, aiming for the area where the smoke was heaviest. Hercules grabbed Cacus and strangled the monster, and was praised throughout the land for his act. According to Virgil in Book VIII of the "Aeneid", Hercules grasped Cacus so tightly that Cacus' eyes popped out and there was no blood left  in his throat: "et angit inhaerens elisos oculos et siccum sanguine guttur". Another version of the myth states that Cacus made the cattle walk backwards so they left a false trail. Hercules drove his remaining cattle past a cave, where Cacus was hiding the stolen ones, and they began calling out to each other. Alternatively, Caca, Cacus' sister, told Hercules where he was. According to Dionysius of Halicarnassus, when the Aborigines and the Arcadians who lived at Pallantium learned of the death of Cacus and saw Hercules, they thought themselves very fortunate in being rid of the former, they were  plucking branches of laurel, crowned both him and themselves with it and their kings invite Hercules to be their guest. In the Roman tradition, Hercules founded an altar after he killed Cacus. Eusebius writes that Heracles erected an altar in the Forum Boarium, to commemorate his killing of Cacus. In the "Aeneid", the Arcadian King Evander recounts this story to Aeneas to explain the rites the people perform yearly to Hercules. This was the Ara Maxima, where later the Forum Boarium, the cattle market of Rome, was held. Hercules had temples in the area, including the still extant Temple of  Hercules Victor. In modern languages. In the Spanish language, the derived form "caco" is a colloquial word for "thief" and a disused word for a very cowardly man.