As artificial intelligence has already mastered the ancient game of Go, researchers are now moving on to complicated games of a more modern variety, like the massively popular MOBA title Dota 2. At this year’s Dota 2 tournament hosted by developer Valve at The International e-sports event, a new bot created by the startup OpenAI managed to defeat Danylo “Dendi” Ishutin, one of the world’s best professional players, live on stage during a 1-on-1 match.
As part of a special demonstration for the crown, the OpenAI bot defeated Dendi with ease in the first of three rounds, with the winner being the first to two kills or destroying an in-game tower. After the AI quickly got the first kill in the second round, the human player gave up and forfeited the rest of the match. Afterwards, Dendi admitted he was surprised at how easily the bot beat a human player, adding that it felt “a little like human, but a little like something else.”
Engineers from OpenAI, which is backed by Tesla and SpaceX CEO Elon Musk, explained that their bot earned a “lifetime” of experience after two weeks of real-time Dota 2 training against itself, eventually working up to go undefeated against other professional players, including Artour “Arteezy” Babaev and Syed “Suma1L” Hassan.
“We’ve coached it to learn just from playing against itself,” said OpenAI researcher Jakub Pachocki. “So we didn’t hard-code in any strategy, we didn’t have it learn from human experts, just from the very beginning, it just keeps playing against a copy of itself. It starts from complete randomness and then it makes very small improvements, and eventually it’s just pro level.”
Dota 2 is normally played as a 5-vs-5 team game, so limiting the bot to a 1-on-1 match greatly reduces the complexity. OpenAI says its next goal is to build a team made up of five bots that can hold its own against a team of top human players.