Gold

Gold is the deluxe currency in Age of Chaos. It is used to buy deluxe buildings for your City, Rare or better equipment, extra forge slots, and faster building/forging/enhancing as well as guaranteeing that forging is successful.

Obtaining Gold
Gold is purchased with real-life money, but can be obtained through gameplay with enough patience. It can be obtained by getting rare drops from Chests, and there are probably a billion other ways I don't know of but I'm just a lowly noob.