Doom 1993/doom 2. Decades of gaming since it came out and STILL nothing has beat the tactile sound of the super shotgun paired with the moans of demons collapsing. Absolutely amazing. though I only have 100+ hours in these 2 games combined they are a must play.
Closest I can think of is the engineers plasma gun in Deep Rock Galactic which is my #2 must play game. Its SO fun and a successful grapple + special powder x2 + grapple + skull crusher to get into a nitra vein when the engie isn't around is so incredibly satisfying. 1700 hours shows I love it so much.
Minecraft. Need I say more? rough estimate as a lot hasn't been tracked but 1500 on switch and 153 days on prismlauncher is around 5,000 hours in this silly block game.
EDIT: didn't expect the variety of games in this thread, very interesting