And K3.1 Pro builds the whole game, not just the part users described.
Seven in ten prompts never ask for a win, a level, a goal, or a mission. On those, 53% of K3.1 Pro's games can still be finished, against 28% of K3's. When the prompt does ask for an ending, it's 84% against 71%.
It isn't down to who was prompting, either. Among the users who prompted both models, 73% of K3.1 Pro's games could be finished, against 30% of K3's.