Go right! Go right! Go right!” the students were shouting. “Now down, down, down, downdowndown!” A few had lifted themselves onto their knees and were pounding invisible keyboards in front of them. “Whoa!” they yelled in unison, some of them instinctively ducking as Doyle’s sprite narrowly avoided a patrolling enemy.

Had he taught anything?

snap up more points and calmly offered a piece of advice. “That extra movement cost you some precious time, Al,” he said, sounding almost professorial. “There are more points up there than what you need to finish.