Nier Replicant Codex: Tag-

The Codex reveals that the Lunar Tear isn't just a pretty flower. It is a genetically modified organism created after humanity died out, designed to be the only beautiful thing left in a cursed world.

But after you finish Route B (and gain the ability to understand Shades), the Codex becomes a tragedy. Tag- NieR Replicant codex

Reading the Codex changes the final shot of the game. You stop seeing a field of flowers and start seeing a graveyard of human ambition. NieR Replicant is a game that demands you to be a detective. If you ignore the Codex, you play a simple action RPG about saving your sister. But if you pause the game, scroll to the right, and start reading the weapon lore... The Codex reveals that the Lunar Tear isn't

Initially, the Codex describes Weiss as a "forbidden tome" of unknown origin. But if you dig deep enough (specifically, by reading the Grimoire NieR companion book, which the Ver.1.22 codex references), the weapon stories for the "Fool's" weapons tell the truth. Reading the Codex changes the final shot of the game