In my household, we do not celebrate Christmas. There is no Santa.
There is only the Solstice Night, when the sun is swallowed up and then slowly regurgitated by Sizzlepiss, the Solstice Opossum. She crawls up your duct work to leave "presents" in your shoes. If you've been naughty, she doesn't leave coal - she chews open your gas lines. Place the rotting scraps of your heathen feasts by your trash bins now and you may yet please her.
Sizzlepissmas is also celebrated in the City-State of Carrow, where gifts are exchanged much you do for your holidays. In honor, here's a random table for you. Technically, I made it up for a post on another forum, but it's the thought that counts.
So the PCs have been captured by some subterranean "savage" culture, like gnolls or orcs. Instead of outright execution, the PCs are sealed inside the skull of a giant, which is then filled with either:
1. A mild acid (will ruin cloth and paper, removes all body hair, permanent scarring over entire body),
2. Cave Bees (like normal bees but deal with fungi spores instead of pollen),
3. Gnoll pups,
4. Cave Honey Mead (think bourbon with traces of LSD in it),
6. Snakes and chicken eggs,
7. Snakes and live chickens,
8. Hallucinogenic Mushrooms,
9. Rotting meat,
10. A candle, some dice, a couple hunks of meat and a kobold who just happened to get caught the very same morning.