We see a mistake in the scene where Piper changes her body with the Zen Master in limbo. After they have changed bodies the Zen Master, that is now in Piper's body, says "Where's the dragon blade?". Just after that we see Piper in the Zen Master's body, and Yen-Lo is talking about the blade "I was telling you how I stole the blade from your daugther". If Yen-Lo was talking about the blade with the blade in his hands and suddenly the Zen Master went away, why did the Zen Master ask about the blade when he gets into Piper body? He knew already that Yen-Lo had the blade.