Thermortian Sand Worm

The Thermortian Sand Worm was a type of creature which did eat, but whose internal organs would turn into sludge if fed water.

When trapped in a labyrinth, Romana was asked the riddle "Feed me and I live, give me drink and I die" by Taureau the minotaur. She gave the answer as Thermortian Sand Worm, but Taureau was expecting the answer fire. (IDW: The Forgotten)