Attention: You must have used the market or made a Steam purchase within the last 30 days or when you open the 4-pack the games will become untradable. If this happens, your collateral is forfeit and you will be stuck with the 3 remaining gift copies.
Space Engineers - 4keys
How unpacking 4-packs works:
Attention: You must have used the market or made a Steam purchase within the last 30 days or when you open the 4-pack the games will become untradable. If this happens, your collateral is forfeit and you will be stuck with the 3 remaining gift copies.