Spruce Mineshafts.jar is a release file of the Minecraft mod Spruce Mineshafts for Forge, made for Minecraft 1.16.5. It was published on May 19, 2021 and is 0.1 MB in size. For the full description, screenshots and every other version, visit the Spruce Mineshafts mod page.
How to install: Put the .jar into the mods folder (.minecraft/mods) and start Minecraft with the matching mod loader profile.