-enemy player spawned an clown at the start of the game without losing any keys, he could use them later in game.
At the end of a turn few keys from bank are added to the available keys. In this example player had 21 keys in bank before ending the turn, then after ending the turn 3 of those keys moved. If you compare his and your keys, you will see you have 4 keys more in total (18+3 < 4+21).
Hey there! As Dolphin had answered this, I’ll go ahead and close this thread for now. 