I recently booted up Half-Life 2 to replay it. I have played the absolute shit out of this game before, so 60% of it just feels like a drag to me now. It was such an amazing game but it's sort of spoiled for me after I've played it too much.
I also discovered ULTRAKILL a few months ago. I feel like I could play that game forever. It has tons of content, weapon combinations and higher difficulties with different enemy behaviour.
Do any of you have more game suggestions like Ultrakill? A really replayable singleplayer game.
!!BTW I don't mean online multiplayer games or games similar to candy crush!!
Classic Doom 1 and 2. There's gotta be over 100 levels if you count TNT and Plutonia, which I think were sold as Final Doom? Anyway, if you just get the base games for 1 and 2, there are thousands upon thousands of community made maps, including some total conversions, so you can play new Doom content until it physically pains you to continue.
Of course, I feel obligated to mention that even though it would be super easy to pirate the WAD files and play with a free modern source port like GZDoom, like absolutely trivial to find copies of DOOM.WAD and DOOM2.WAD floating around the net, probably showing up easily on Archive.org, but... Um... Where was I going with this? Oh, right, don't pirate. Cheap on GOG last I knew.