Before and After

From Halopedia, the Halo wiki

Before and After is an achievement in Halo: The Master Chief Collection. It is unlocked by completing every level of Halo: Combat Evolved Anniversary having seen it both classic and remastered graphics mode. Viewing each graphics mode for even a second is enough to satisfy the achievement's requirements. The achievement is worth 10 Gamerscore and can be unlocked on any difficulty.