https://arstechnica.com/gaming/2019/04/openai-bot-crushes-dota-2-champions-and-now-anyone-can-play-against-it/

Over the past several years, OpenAI, a startup with the mission of ensuring that "artificial general intelligence benefits all of humanity," has been developing a machine-learning-driven bot to play Dota 2, the greatest game in the universe. Starting from a very cut-down version of the full game, the bot has been developed over the years through playing millions upon millions of matches against itself, learning not just how to play the five-on-five team game but how to win, consistently.

We've been able to watch the bot's development over a number of show matches, with each one using a more complete version of a game and more skilled human opponents. This culminated in what's expected to be the final show match over the weekend, when OpenAI Five was pitted in a best-of-three match against OG, the team that won the biggest competition in all of esports last year, The International.