Serious Sam 3: BFE
https://www.steamgifts.com/giveaway/L5fo9/serious-sam-3-bfe

Serious Sam HD: The First Encounter
https://www.steamgifts.com/giveaway/Oj8bI/serious-sam-hd-the-first-encounter

Serious Sam HD: The Second Encounter
https://www.steamgifts.com/giveaway/DMRLf/serious-sam-hd-the-second-encounter

Serious Sam HD: The First Encounter
https://www.steamgifts.com/giveaway/zE6M3/serious-sam-hd-the-first-encounter

Valiant Hearts: The Great War™ / Soldats Inconnus : Mémoires de la Grande Guerre™
https://www.steamgifts.com/giveaway/9rR06/valiant-hearts-the-great-war-soldats-inconnus-memoires-de-la-grande-guerre