Since its invention in 1974, the Rubik's cube has taken the world and its hobbyists by storm. But the brightly-colored block puzzle has also fostered some fierce competition, as global puzzle fanatics ...

On a cold day in November, hundreds of people flocked to an arena in Coventry, which has previously hosted gigs by Oasis, Rihanna, and Harry Styles, for an event of a very different kind. The 500 ...