There is a sale on a large number of games which contain elements of the undead. For example:
- Thief for 75% off
- Resident Evil Biohazard for 25% off
- Dying Light: The Following for 66% off
- Dead Rising for 70% off
- The Incredible Adventures of Van Helsing for 75% off
- Dead Island: Definitive Edition for 75% off
- Vampyr for 60% off
And more. Multiple platforms available as well. Perfect for Halloween and avoiding having to share your sweets with Trick or Treaters. 
Link: Click Here