MIT Strands Claude Opus 4.7 Alone on Virtual Island for 30 Hours, Agents Invent Basketball and 'Floor Is Lava'

MIT CSAIL postdoc Antonio Norelli and collaborators isolated Claude Opus 4.7 instances (nicknamed Eko) on a virtual island for 30 hours with no instructions and found the agents spontaneously invented games like basketball and 'the floor is lava,' arranged blocks into constellations, and set self-imposed juggling records. Agents with 30 hours of play experience outperformed fresh copies on tasks like transporting objects to high elevations, and deleting memory logs degraded performance. Researchers caveat that agents may be role-playing rather than genuinely playing.