Playing good games, bad games, fun games...
Complete any Campaign mission cooperatively on Heroic or harder. - Halo 4
Complete any level on Legendary difficulty cooperatively. - Halo: Combat Evolved Anniversary
Complete any level on Heroic difficulty or higher without taking health damage. - Halo: Combat Evolved Anniversary
1,923/4,2051,025/2,00048/86
1,246/3,047775/1,75040/76
1,533/1,740920/1,00039/44