EMT_x256 is a release file of the Minecraft resource pack ExtremeMaterialTexture, made for Minecraft 1.12.2. It was published on July 22, 2022 and is 266.1 MB in size. For the full description, screenshots and every other version, visit the ExtremeMaterialTexture resource pack page.
How to install: Put the .zip into .minecraft/resourcepacks (do not extract it) and enable it under Options → Resource Packs.
