There are currently four different Wrenches: the Red Wrench, Green Wrench. The Goblin Tinkerer is an NPC that sells several unique items, as well as providing the Reforge function. He can be acquired after a Goblin Army has been defeated, spawning randomly in open areas in the Cavern layer (Underground layer in the Don't Dig Up and Everything seeds.) He will appear to be bound at first, and like the Mechanic, Wizard, Golfer, Tavernkeep, Angler, and Stylist, talking.