The Evil Within 2
The original The Evil Within had quite a bit of DLC! Additional adventures called The Assignment, The Consequence, and The Executioner gave people more to do in this spooky world. While The Evil Within 2 does a good job of wrapping things up, more or less, it was a standalone experience. But given how well it was received and how much people enjoyed it, it is a shame that it didn't give people additional horrors to experience.