Bili Under the Hill is a children's book about a hero named Bili. He went on an adventure, was given three answers, and came back to find ten years had passed and he possesses a bag of gold that is always full.
Elayne Trakand is reminded of the story when Moiraine Damodred tells her about the twisted redstone doorframe ter'angreal in the Stone of Tear that one may enter to get three true answers to three questions. Matrim Cauthon is reminded of the tale when Egwene al'Vere tells him the story. After Mat exits the twisted red doorway, he worries that they will go back upstairs to find ten years gone like Bili in the story. Tuon references the three answers when she asks if Mat believes that if you sleep on Old Hob's Hill under a full moon, the snakes will give you true answers to three questions, or that foxes steal people's skins and take the nourishment from food so you can starve to death while eating your fill. The book appears to be a reference to the victims of the Tower of Ghenjei.
Bili appears to be a combination of Bilbo Baggins of Tolkien's The Hobbit, who lived under a hill and had many underground adventures, including playing three rounds of a riddle game with Gollum, before returning home; and legends of adventurers exploring prehistoric mounds who unwittingly enter Faerie worlds and return to find many years have elapsed.