DeepMind's AI can defeat human players in Quake III Arena's Capture the Flag mode

Few games are simpler in principle than capturing the flag (excepting perhaps tag or kick the can). Two teams each have a marker located at their respective bases, and the objective is to capture the other team's marker and return it safely back to their base. What's easily understood by humans is not quite so quickly grasped by machines, though. Where capture the flag is concerned in the video game domain, non-player characters have traditionally been programmed with heuristics and rules affording limited freedom in choice. But AI and machine learning promise to turn this paradigm on its head. In a paper published this week in the journal Science roughly a year following the preprint, researchers at DeepMind, the London-based subsidiary of Google parent company Alphabet, describe a system capable not only of learning how to play capture the flag in Id Software's Quake III Arena, but of devising entirely novel human-level team-based strategies.