nothingness-reborn-1.4.0-21w20a.jar is a release file of the Minecraft mod Nothingness Reborn for Fabric, made for Minecraft 1.17-Snapshot. It was published on May 20, 2021 and is 0 MB in size. For the full description, screenshots and every other version, visit the Nothingness Reborn mod page.
How to install: Put the .jar into the mods folder (.minecraft/mods) and start Minecraft with the matching mod loader profile.