opitems-v1.3-forge-1.16.5.jar is a release file of the Minecraft mod Ssemik's OP Items [Discontinued], made for Minecraft 1.16.5. It was published on October 14, 2022 and is 0.1 MB in size. For the full description, screenshots and every other version, visit the Ssemik's OP Items [Discontinued] mod page.
How to install: Put the .jar into the mods folder (.minecraft/mods) and start Minecraft with the matching mod loader profile.
