Jim's Cap

You need a Painter who happened to roll the name Jim, and then you need him dead, which the game will not let you do directly. Killing a town NPC means arranging an accident: a trap, an explosive bunny, a hostile mob you deliberately let through the door. Lava works, but a deep pool destroys low-rarity drops, so keep the puddle shallow.

If your Painter is called something else there is no way to force it. Renaming him does nothing, and neither does a resource pack that shuffles names around. The check reads the name the game originally assigned, so your only option is to let that one die and hope the replacement rolls right.

Jim is one of the artists who worked on the game. Two other town NPCs carry the same kind of hidden drop, tied to a Guide named Andrew and a Steampunker named Whitney.