Most hours spent on one game?

siege - hands down siege to unlock everything since i got the base version - the grind was madness - thousands of hours spent!

4100 hours of Garry's Mod on this account. About 8000 in my life.

Ive played Minecraft for over 2000 hours, League of Legends 1500 hours and Rainbow Six Siege 200 hours

I have about 1010h in gmod and I think about 1000 on minecraft

1000+ hours on osu! lol
it's really addicting what can i say..

My game with most hours is Garry's Mod with 2600+ hours and then TF2 with 1000+ hours.

shoot i dont even want to know the hours i spent on minecraft and halo reach on xbox lol but pc only 998 hourson garrys mod

I play a lot Starcraft 5000+ i think , the Campaing and multiplayer with friends from the 2001.

ark survival evolved i think it's about 4000 hours by now

Probablt Fallout New Vegas, I played through that game around 4 times with plenty of mods, actually the main story was the last thing I would do.