11 0 0Actions Report Solution Just play the seventh mission, The Library, solo or coop on any difficulty and it will unlock. This is story related, you cannot miss it.You can also unlock these achievements in the mission if you follow the criteria: The That Just Happened achievement in Halo: Combat Evolved Anniversary worth 30 pointsComplete the level “The Library” on Heroic difficulty or higher without dying.The Speed Reader achievement in Halo: Combat Evolved Anniversary worth 71 pointsComplete the level “The Library” on Legendary difficulty in 30 minutes or less.Leave a comment