Junker Goblin

You use jury-rigged tools, bits of string and wires, and a deceptively clever mind to craft just about anything. You gain an attribute boost to Intelligence instead of Charisma, but the free ancestry boost can't also be Intelligence. You become trained in Crafting. If you would automatically become trained in Crafting (from your background or class, for example), you instead become trained in a skill of your choice. You gain the Explosive Engineering feat.