On July 8, 2017, an AI system built by our research company, OpenAI, beat a semipro human player in solo matches of a battle arena video game called Dota 2. One month later, the same AI system beat a professional gamer ranked in the top 50. Three days after that it defeated the No. 1 solo Dota 2 player in the world. And it kept getting better: The Aug. 11 version of our AI beat the Aug. 10 version 60% of the time. Our AI learned to trick its opponents, predict what it couldn’t see and decide when to fight and when to flee.

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