Thought of a new one, lets see if anyone has any interest.
This is a light. Something like the Holy Light of Serra.
It would be very bright, heavy, give -10 resdarkness, but only last for 30 hours.
This would not be a permanent light.
But here's the real kicker. The light has a special power.
Vampires cannot enter changeform while in the same room as someone bearing this light.
Vampires currently in changeform will be slowly and painfully ripped from changeform after 1 tic, leaving them slightly stunned for a moment (same time as bash, dirt kick, or backstab maybe), slightly injured from the unintentional change, and vulnerable to attack.
The cost should be high, like 5000 tokens, and probably shouldn't be sold in Mesilena