How do you beat a world champion?
You need to be playing the right game! Consider Lee Changho, 9p. Even for top professionals, it's almost impossible to win a single game of Go against Lee. You can study for years, read all the books, replay all the professional games and solve all the life and death problems, and still not be able to beat him. Some Korean Go professionals have even taken up his hobby, tennis, just so they can get a chance to play him and be able to boast "I played Lee Changho yesterday and crushed him!"
Well if you can't get a tennis date with Lee Changho, here's another game that lets you beat the best. After you learn Dango and play just a few games to get the idea, you can easily crush any professional Go player. There are no books, no life and death problems and it's hard to even find a game record to study. You just need a bit of experience, intuition, memory and a sense of shape. And Dango is a lot easier than tennis!