The Open AI guys made a very impressive Dota 2 AI that trained itself through self play (and against pros), there is a pretty interesting write-up about it:
To shed some light on why they won, they chose a character (Shadow Fiend) that heavily relies on tight timings to execute moves. Naturally, AIs beat humans in events where timing is the key differentiator. Even so it’s quite impressive
https://blog.openai.com/dota-2/