A couple years after DeepMind released AlphaZero, researchers trained EfficientZero to be very data-efficient, where if given two hours to play an unseen Atari game, the model would beat a novice human, but this doesn't necessarily mean the model was more sample-efficient than humans—it depends on how you measure, because EfficientZero plays dozens of simulated games in its head for each real-world game step.