A list of the games featured thus far. Courtesy of
this thread on the GOG forums.
The Witcher: Wild Hunt: -50% (first batch: 100 units)
Ys Origin: -70% (25 units)
Ys VI - The Ark of Napishtim: -70% (25 units)
Serpent in the Staglands: -40% (25 units)
Xenonauts: -66% (40 units)
A Bird Story: -60% (25 units) (thanks Zeffyr and Taro94)
Dungeons 2: -75% (thanks Cavalary)
Renowned Explorers - International Society: -50% (40 units)
Hyperdimension Neptunia Re;Birth1: -80% (thanks mrkgnao)
Dead Synchronity - Tomorrow comes Today -75% (25 units)
King of Dragon Pass: -75% (25 units)
Else Heart.Break(): -60% (25 units)
RuneStone Keeper: -50% (25 units)
Saints Row 2: -75% (25 units)
Dreamfall Chapters - Season Pass: -75% (40 units)
Saints Row: The Third - Full Package: -75% (40 units) (thanks Grargar)
Monkey Island Classics: -80% (50 units) (thanks Grargar)
Pillars of Eternity: Hero Edition: -60% (60 units)
Democracy 3: -75% (25 units)
Crookz: The Big Heist: -66% (25 units)
Infinifactory: -50% (25 units)
HuniePop: -60% (25 units)
Recettear: -80% (50 units)
The Masterplan: -75% (25 units)
Two Worlds: Epic Edition: -85% (25 units)
The Last Tinker: City of Colors: -80% (25 units)
Jotun: -40% (40 units) - new game
Van Helsing II Complete Pack: -75% (40 units) (thanks Grargar)
Victor Vran: -60% (60 units)
Darkest Dungeon: -20% (25 units)
OlliOlli 2: -75% (40 units)
The Dig: -75% (50 units)
System Shock: -60% (60 units)
Lords of Xulima: -60% (40 units)
The Wolf Among Us: -80% (40 units)
Sins of a Solar Empire: Rebellion Ultimate Edition: -75% (25 units)
The Witcher 1: -85% (40 units)
Lego Batman: The Video Game: -75% (25 units)
Outlaws: -75% (50 units)
Chaos Reborn: -60% (40 units)
Titan Souls: -75% (25 units)
Darksiders: -80% (40 units)
Big Pharma: -60% (25 units)
Shadows: Heretic Kingdoms -40% (40 units)