spectrums.jar-(old)-forge-1.20.1.jar is a release file of the Minecraft mod SPECTRUMS for Forge, made for Minecraft 1.20.1. It was published on July 11, 2025 and is 71 MB in size. For the full description, screenshots and every other version, visit the SPECTRUMS mod page.
How to install: Put the .jar into the mods folder (.minecraft/mods) and start Minecraft with the matching mod loader profile.
