Help me mess with my player

[Rechan]

One caveat: The PC gave only his first name. (Granted, he has never said his last name, so). Therefore the hold on the Player may not be as significant as if he had said his full name, you know.

 

[Shroomy]

Two words: Evil Twin

 

[Cryptos]

I'd be tempted to look into the concept of Truenames and see what sorts of things a person could do with them in legend and fiction, and go from there.

I'd go with this, having the person's spoken name in the jar gives them power over that person, with the merchant-being either working for a major upcoming enemy or selling it to the major upcoming villain. The villain got a prophecy that their plans would be foiled by the character, and so they are going out of their way to acquire the means to avoid the prophecy.

Alternatively, I would make it seem like the above, have an entire series of adventures where the side-quest or even the main objective is finding the old man and getting the name jar back, only to have it turn out that the merchant was just an eccentric, crazy old man and it's just an ordinary jar or something minor, like a jar that cast the light spell when someone speaks into it (if you had any special effects take place when the deed was done.) Maybe even have the story's villain also hear about the jar, and have both sides trying to acquire it, attempting to track down the merchant across the countryside and getting into all manner of strange adventures as a result.

Actually, I think I would prefer the latter.