Dota 2 boasts the highest ARPU (average monthly revenue per active user) among the MOBA genre. Why? I claim that crowdfunding and crowdsourcing, the secret sauce of Dota 2 if you will, are the keys to this success.
You can also view the presentation video at https://youtu.be/ETuwQ9sc2w8
The presentation is based on my blog post The secret sauce of Dota 2: crowdsourcing and crowdfunding at http://www.kilkku.com/blog/2015/09/the-secret-sauce-of-dota-2-crowdsourcing-and-crowdfunding/