Kotaku editor-in-chief Stephen Totilo called The Library Halo: Combat Evolved's most notorious level. An entry on Halopedia referred to it as one of the least popular levels in the Halo series. The Library is the hardest level in the game by far, a cruel gauntlet featuring seemingly never-ending waves of Halo's toughest enemies. I love The Library. I think it's secretly one of the best levels in Halo history. Want to know why?