While there's a fairly sizable learning curve, DOTA 2 offers something for any serious or casual online gamer. There's a massive hero pool of over 100 unique characters. The best way I've heard it described was in the movie "Free to Play," as a 'cross between soccer and chess'. As the title of the said movie blatantly states, the game is free-to-play. However, there are many optional cosmetic in-game items that one is able to buy within a $5-$15 range (i.e. a crown, sword, shield, etc). The matches are 5 vs 5 players, each with a unique character with their own strengths and weaknesses. No duplicate heroes in a match are allowed. Communication with your team during a match is paramount in order to win. That being said, there will be occasions when you run into verbally abusive players, which you are allowed to report. But in hindsight, give this game a try. Seriously.
kthxbai