"Papa, let's play a versus game," he says. So I build a secret hideout, start mining, have stone gear, when bam! Proceeds to use commands to teleport to me while in creative mode and fly around and fill up my mine with stone while I try in vain to kill him. Then he agrees to quit and teleports away. Later he uses spectator mode to find my base, and equips himself like I am. I killed his cheating little butt.