playing multiplayer on mac

[norman1994civ5]

I bought civ 5 for the mac on the app store. The app store name of the game is campaign mode so i'm pretty sure that is does not have multiplayer. I would really like to play with others. So would anyone know how I can play this civ 5 mac game online without buying something else? Also is there a way that I could play civ with pc players also?
Thanks for the help