Pre-Witched - S3-E17
Plot hole: One of the sisters asks why the familiar doesn't just jump in front of a bus 5 times, another responds with "we're the only ones strong enough to kill him." If they are the only ones strong enough to kill him, then how come two scenes later he falls on a knife during a fight with Phoebe and dies? If a knife can kill him then it doesn't make sense that he seeks out the charmed ones.
Plot hole: When Phoebe and Cole are using the apple peel to find out her true love how does she not recognize that it is Cole? Even with the mask it's very clear that it is him.
Suggested correction: I was thinking the same, but it's possible she thought he was an ancestor/past life of Cole. When she visited her own past life, she recognized everyone there because of their "souls" so maybe she thought the same with him. Although you'd think they'd acknowledge that a little.