I don't have any like what you describe. You could almost say that occasionally GTA Online falls in this category if all I'm doing is just goofing around. And I mainly just play Killer Instinct. But my dad is addicted to a "Blizzard solution" called War of Nations for the iPad.

The most recent for me is Letter Quest on endless mode. Before that, the most recent Gauntlet.

Dont really understand your problem. Aside from diablo 3, those games still provide challenge to keep me engaged on the game. Diablo3 on the other hand really needs some real challenge for high lvl run

I often fell asleep in the middle of combat in Diablo 3. So as a screen saver it isn't particularly captivating.

It seems the vast majority of games I play nowadays fall in that category. Far Cry, Rocket league, Valley. All just basically excuses to reduce my youtube queue.