DeepMind says it has created the first artificial intelligence to reach the top league of one of the most popular esport video games.
It says Starcraft 2 had posed a tougher AI challenge than chess and other board games, in part because opponents' pieces were often hidden from view.
Publication in the peer-reviewed journal Nature allows the London-based lab to claim a new milestone.
But some pro-gamers have mixed feelings about it claiming Grandmaster status.
DeepMind - which is owned by Google's parent company Alphabet - said the development of AlphaStar would help it develop other AI tools which should ultimately benefit humanity.
"One of the key things we're really excited about is that Starcraft raises a lot of challenges that you actually see in real-world problems," said Dave Silver, who leads the lab's reinforcement learning research group.
"We see Starcraft as a benchmark domain to understand the science of AI, and advance in our quest to build better AI systems."
DeepMind says that examples of technologies that might one day benefit from its new insights include robots, self-driving cars and virtual assistants, which all need to make decisions based on "imperfectly observed information".