Sourpuss is a machine in Fiend Folio, a mod for The Binding of Isaac.
Permanently smelts the currently held rock trinket in exchange for 1.5 Soul Hearts.
When destroyed, has a 25% chance to drop 2-4 random coins. If this chance fails, there's an additional 10% chance for a random rock trinket.
If destroyed in The Chest or Dark Room, it will always drop a random rock trinket.
Exclusive to Golem's Subway. Appears on every even-numbered floor.