Valve has detailed the Steam Holiday Auction, a limited time event allowing users to trade community items like Trading Cards for full games including Civilization: Beyond Earth, This War of Mine and more.
Starting this coming Monday, Steam account holders can trade in unused items for Steam Gems that can be used to bid on games – including the aforementioned recent releases.
The first auction takes place on Monday morning, with a new auction kicking off every 45 minutes until Thursday December 18th. According to PayPal, the 18th is also when Valve plans to launch its Winter sale.
Full details can be found on the new page for the event on the Steam Store.

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