Snakes

When Admetus reigned over Pherae, Apollo served him as his thrall, while Admetus wooed Alcestis, daughter of Pelias. Now Pelias had promised to give his daughter to him who should yoke a lion and a boar to a car, and Apollo yoked and gave them to Admetus, who brought them to Pelias and so obtained Alcestis. But in offering a sacrifice at his marriage, he forgot to sacrifice to Artemis; therefore when he opened the marriage chamber he found it full of coiled snakes. Apollo bade him appease the goddess and obtained as a favour of the Fates that, when Admetus should be about to die, he might be released from death if someone should choose voluntarily to die for him. And when the day of his death came neither his father nor his mother would die for him, but Alcestis died in his stead. But the Maiden sent her up again, or, as some say, Hercules fought with Hades and brought her up to him.


- Pseudo-Apollodorus, The Library, Book 1, Chapter 9, Section 15