What's a single player PC game you can't get enough of?

Dying Light, absolutely fantastic pakour zombie smasher with one of the best cities in gaming. Bought it originally (on a disc) many years ago and played it so much the disc died and I was inconsolable until Epic gave away the ultimate edition and I was finally able to play The Following DLC.

Now I go and look at Dying Light 2 on Steam and wish my stupid country wasn't so damn expensive, even on sale at 50% off it still costs almost as much as a brand new AAA game in the states. Regional pricing my ass, we always get stung so hard for tech down here.