MegacraftClassicRelease1.0-1.2.zip is a release file of the Minecraft resource pack Megacraft Classic - Be the Block Bomber!, made for Minecraft 1.2.5. It was published on February 6, 2014 and is 1.3 MB in size. For the full description, screenshots and every other version, visit the Megacraft Classic - Be the Block Bomber! resource pack page.
How to install: Put the .zip into .minecraft/resourcepacks (do not extract it) and enable it under Options → Resource Packs.