OpenAI Five, a team of AI bots, just beat the reigning Dota 2 champions

An AI-powered Dota 2 team trashed the reigning world champions in a show match this weekend, marking off the latest in a long line of impressive milestones for our future robotic overlords.
It’s an impressive result for the OpenAI Five team, as it seized back to back victories to beat the world champions OG in a 2-0 series at an exhibition match in San Francisco over the weekend. While stars rise and fall in the Dota 2 scene, OG are currently the world champions after a victory at The International 2018, and could well be the best human team in the world.
Meanwhile, the OpenAI Five is a group of bots that have been designed to learn to play Dota 2 on their own. Their secret? Practice. Taking to the stage, OpenAI chairman said that OpenAI Five has played some 45,000 years in the last 10 months, improving a little with every game, and learning a bit more with every scenario.
Related: Best PC Games
OG played like world champions in the first game, pushing for every single advantage until OpenAI Five managed to snatch the win. It’s tough to know how much was OG’s fault. While they played decently, they did make a lot of unusual plays. However, by the second game the fight had gone out of them, and the heroic robots grabbed an early lead and turned it into a solid by-the-numbers win.
OpenAI made a few unique plays that seemed to have paid off. The bots made several early buybacks. A buyback is when the characters splash the in-game cash to reset their respawn timer, immediately charging back into the fray. Usually, players will only buyback into the game to counter an attack on the base as it’s a costly strategy that can severely hinder growth.
A push on the base is often an end-game situation. By buying back at seemingly random times, OpenAI’s buyback didn’t make any sense. It seemed to show the OpenAI’s preference for short-term gains over a long-term strategy. Or at least, it appeared that way until the AI used those buybacks to build a solid lead.
Related: Best FPS Games
AI researcher and Dota 2 fan Mike Cook tweeted throughout the event, and the thread is worth reading for contextualising a lot of what happened.
Major differences to last game – OG aren't doing enough to disrupt the AI across the map, and their heroes are a lot weaker. The draft might have some potential later on but it really depends on whether we get there. Ceb is… oof. #openaifive
— mike cook (@mtrc) April 13, 2019
This wraps up the public demonstration stage for OpenAI. Next, the researchers behind it have new opponents in mind: the public.A mode called Arena will be open for three days from April 18, letting the public have a crack at at the champion-beating AI team. Then, in the future will be a program to let humans play alongside the AI, letting you watch them at work while they presumably out-play you.
Impressively, the OpenAI isn’t even built for the purpose of playing Dota 2. It’s a general purpose AI that can supposedly learn how to do just about everything. Dota 2 is just a pedestal for the team to show what they can do. It doesn’t make it any less impressive, especially as last night I lost three games against really fleshy humans.