The Mass Update is a release file of the Minecraft mod Subnautica Flow for Forge, made for Minecraft 1.20.1. It was published on June 22, 2024 and is 16.9 MB in size. For the full description, screenshots and every other version, visit the Subnautica Flow mod page.
How to install: Put the .jar into the mods folder (.minecraft/mods) and start Minecraft with the matching mod loader profile.