While playing with Chop Chop trying to go through all the Heroic Challenges, I was unable to Save the Sheep because they disappeared. The same thing happened when I tried to Save the Sheep with Double Trouble but I had no problem with VooDoo. What is causing the sheep to disappear? The only thing they have in common is a glowing from Chop Chop's sword and Double Troubles skirt. Is there a connection?