i havent played any "traditionally" hard games lately, except for this roguelike called Cogmind. it's not so much "hard" as it is incredibly unforgiving of small mistakes. since its turn based, theres no mechanical pressure for you to sweat over, but you can make one small decision and watch your whole run disintegrate in real time. despite this its still incredibly fun.

in terms of "traditionally" hard games, id say Ultrakill - specifically my attempts to get the highest rank on the highest difficulty on every level. its a gruelling experience that took a month of my life before i had to call it quits due to irl circumstances. its also incredibly fun, but for totally different reasons from Cogmind lol