Disco Elysium is 75% off.
Prey (and Mooncrash) are 75% off. Most other Arkane games are too, and they're all top notch (except Redfall :/)
Killer7 is 75% off.
Ace Combat 7 is 85% off.
Dying Light (and The Following expansion) are 80% off.
CONTROL is 75% off.
All the Deus Ex games are >80% off, really can't go wrong here.
Pillars of Eternity I and II are 75% off.
Lots of great deals on high-profile games this sale, and I highly recommend everything on this list.