Unrefined Astraen Crystals (UAC) is a common and untradable currency. It can be earnt from playing both unranked and ranked versions of the game, and is a core component in crafting skins, forging marks and purchasing upgrades.
The purpose of UAC is to have an untradable pre-requisite for crafting and forging, requiring players to actively play the game in order to get the most out of the economy. This means players who are purely trying to extract value from the ecosystem through mark or skin arbitrage must also play the game in order to participate.