You should also read the specific system requirements for each pack before purchasing as some packs have higher requirements than others. YOU DO NOT NEED TO DOWNLOAD THE LEGACY EDITION IF YOUR MAC IS A 2012 MODEL OR LATER. You will need to run the Legacy Edition of the game. *If your Mac is a 2011 or earlier model it is not Metal compatible. Minimum OS -macOS El Capitan (10.11) Metal compatible*.However, these are the recommended requirements which are more relevant when you start adding in Expansion Packs, Stuff Packs and Game Packs:
First of all, make sure your Mac meets the minimum requirements: