Nier Replicant Remaster Ver. 1.22474487139 features a number of permanent and missable events. You should be mindful of them before proceeding in points-of-no-return to avoid missing out on important items, equipment, and cutscenes in the game.
Ending D will erase all saved game data.
Watching Ending D will erase all of your saved game data permanently. There is no way to retrieve them afterwards so be careful of selecting the option to watch this ending during your playthrough if you have not unlocked all other endings yet.
You cannot use character names you already used after watching Ending D.
After all of your game data is erased after watching Ending D, you will not be able to use character names used in deleted save files when starting a new game again.
Certain quests can only be completed in the first playthrough.
Note that there are some sub quests that will only be available during the first story route (Kid Nier). Progressing through the second story route (Adult Nier) locks you out of them permanently so it is worth clearing them as soon as possible.
When playing as Kid NieR, you can receive letters from Jonah. After becoming Adult NieR, you won’t be able to revisit and experience events exclusive to Kid NieR.
Some wild animals such as the sheep and deer can only be found as Kid NieR.
The Cliff Village will be inaccessible after defeating Wendy.
After beating Wendy, you will not be able to enter the Cliff Village until the second story route (Adult Nier). This prevents you from getting certain items like the one-handed sword Nobuyushi and the Eagle Egg until you progress to the second story route in the game.