Earlier this month, GOG launched their annual Summer Sale, which is easily their biggest sale of the year. In just a few short days, the sale will be coming to an end (on the 20th), but the site has announced another free giveaway that you can unlock when you make a purchase. If you spend $10 or more in total, you will unlock a free copy of Alan Wake's American Nightmare into your GOG library, which is yours to keep forever.
Any money you have spent to this point counts towards the unlock. The sale features a ton of great games at massive discounts including The Witcher 3: Wild Hunt, Dragon Age: Origins Ultimate Edition, and Dragon's Dogma: Dark Arisen plus pre-orders have already opened up for Tacoma and Hellblade: Senua's Sacrifice, so there are plenty of ways to unlock American Nightmare.
GOG's Summer Sale is on now and runs until Tuesday, June 20th, 2017 at 12:59 PM UTC / 5:59 AM PDT / 8:59 AM EDT / 2:59 PM CEST.