In 1998, Xu offered an optional course in lantern riddles that was quite popular among college students.
"You have to go along the right track of the riddle maker's thought," he says. "The greatest appeal of the game is not simply hitting the right answer, but following the riddle maker's thought processes and obscure clues, just like a hunter. You should know your opponent and yourself well."
Each riddle must have an answer.
"A riddle that no one can answer is a total failure," say Xu.
There are about 20 methods to solve different lantern riddles, based on the variation of the pronunciation, shape and meaning of Chinese characters. The better ones require knowledge of history and culture.
The key could be a single word, a line from a poem, a historical event, a place name or object.
The basic rule about a lantern riddle is that a word in the riddle cannot appear again in the answer, but there should be a sort of relation.
