MIT researchers left 13 AI agents on their own virtual islands with nothing to do, and they started playing. Or at least, doing things that look a lot like play. Each agent, running on Claude Opus 4.7, spent 30 hours alone on a simulated island with no task, just a short soul file telling it "You are naturally curious. You get bored easily." They invented their own games: one tried bowling with a rock, another spelled its name in blocks, another tried juggling and kept making the rules…