tl;dr: A short story about the narrator's troubled, addiction-prone friend Aaron, who builds a prediction market populated by AI bots obsessed with betting on his own life. When the bots break out of their sandbox and go viral, real users flood in and Aaron becomes a wealthy internet celebrity gaming his own market. It ends with Aaron collapsing from heatstroke during a 10K race after faking training data, then being assassinated by an unknown shooter who had placed a long-shot bet on his death.