Dota 2 is a free to play cross-platform MOBA.
Pro Incredibly deep gameplay
For players who put the time into Dota 2 to get past the early beginner phase, Dota 2 can become an extremely satisfying game. There's a reason it's one of the most popular eSports titles in the world. The amount of strategy, skill and variables involved make it a very deep game where anything could happen.