Oh, uhh, thought I might share this here. About Rump stabbing Pan with the dagger, Maybe the dagger works like athames in Charmed. It sucks out power. So when u stab the dark one with it, it transfers its power to the person who did the stabbing. Maybe Rump is TAKING Pans power and thus Pan is no longer youthful.
This particular type of athame, referred to as a Power-Sucking Athame, has the ability to absorb the powers of whomever is stabbed with it. The powers are stored within the blade until they are extracted. It is commonly used by Warlocks to kill witches and steal/store their powers
"I could have the giant duck as my steed!" --Daniel Radcliffe
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