Goblin Tinkerer

The Goblin Tinker is an NPC, who must be saved by the player after a Goblin army has been defeated. His spawn location is completely random, but he has been observed to spawn mostly in the Cavern layer. He will randomly spawn near you while you are exploring. Talking to him in this state will free him, and he will wander the area until he gets killed by any nearby enemy or hazard, or until you move far enough from him. After that, he will move into an available house like any normal NPC.

Goblin Tinker has the option to reforge a weapon, tool, or accessory for a variable price in Gold.

Once the Goblin Tinker has moved into a house, he will sell the following:

Quotes

 * "Hey, does your hat need a motor? I think I have a motor that would fit exactly in that hat."
 * "YES, gold is stronger than iron. What are they teaching these humans nowadays?" (in reference to Minecraft as well as real life where gold is slightly less sturdy than the tinfoil around a baked potato)
 * "You know, that mining helmet-flipper combination was a much better idea on paper."
 * "Yo, I heard you like rockets and running boots, so I put some rockets in your running boots."
 * "Silence is golden. Duct tape is silver."
 * "Now that I'm an outcast, can I throw away the spiked balls? My pockets hurt."
 * "Goblins are very easy to anger. In fact, they'd start a war over cloth!" (references that you can use tattered cloth to summon a goblin army)
 * "I just finished my newest creation! This version doesn't explode violently if you breathe on it too hard."
 * "I thought you'd be taller."
 * "Hey..what's [Mechanic] up to? Have you...have you talked to her, by chance?" (only when the Mechanic is present)
 * "I can't believe they tied me up and left me here just for pointing out they weren't going east!"(Referring to the fact that the visual in Terraria is facing South, and West and East are thus swapped from their usual directions)
 * "Do you know why we carry around these spiky balls? Because I don't."
 * "Looking for a gadgets expert? I'm your goblin!"