MaS-RT 1.3.zip is a beta file of the Minecraft resource pack Mine and Slash - ReTexture x16, made for Minecraft 1.14.4. It was published on October 2, 2019 and is 2 MB in size. Pre-release builds can contain bugs — back up your world before installing. For the full description, screenshots and every other version, visit the Mine and Slash - ReTexture x16 resource pack page.
How to install: Put the .zip into .minecraft/resourcepacks (do not extract it) and enable it under Options → Resource Packs.