Calumny Pearl
Place it underneath your tongue and you entirely believe the first lie told to you.
Urgrip Wikt (worried peasant, infected with the Goblin Curse, exceedingly poor) offers it as payment if PCs resolve Galgenbeck's goblin problem. Unknown to him, this is what the heirloom is.
Connections
Gaps / Expansion Notes
Whether there are other Calumny Pearls in the world, and who originally crafted them, is open.