I remember about five or six years ago, when I first discovered The Worlds Hardest Game. Boy, that was certainly a struggle.
And of course, who can forget Dark Souls, or Dark Souls II, or Dark Souls III? While I never played any of the Dark Souls games, they were certainly infamous among the gaming community.
xenonVirus. It's kind of hard to define the world's hardest game, because everything is subjective depending on who you ask.