Revealing mistake: In the beginning of the episode, Yenlo and Anling are fighting with swords. After Yenlo says, "I'm going to kill him, Anling. And then I'm going to kill you," Anling stabs him with her sword. Yenlos' wound is very bloody, but there is no blood on Anling's sword at all. (00:04:25)Jason Hoffman
Plot hole: When Yen lo enters the manor in the attic. Where did the water on the floor he comes through come from? Windows were closed, no visible leak, and the sister took precautions to make sure there was no water in the house. Also after he attacks and gets the dragon blade, he exits the house through the sink filled with water. Piper had already said to make sure there was no surfaces of water in the house and had Phoebe and Paige shut the water main off.
Other mistake: Yenlo explains that he escaped limbo through the water in the clouds. And the yen master says there is no other water around. So why do the girls come in through a cave? If they have to leave through the water in the clouds they should enter through the clouds.brianjr0412