KSP. I colonized almost the entire system on chemical rockets alone with bases and ISRU fuel depots orbiting the smaller moons (I’d have to go to each base, do some mining, and refill the orbiting tanker station before every long mission so it’s ready when I got there). I’m not at my PC but last I checked it was a couple thousand hours.
Probably counterstrike back in the day, possibly battlefield 2 including the Project Reality mod. That was back when gametime wasn’t really tracked and I had a lot more spare time Possibly WoW, but I only played for a couple of years or less and for a few hours a day at most.
Currently my highest is Forza Horison 5 with like 1200 hours. Have a few others with 500+ hours although a few are inflated at least 100+ hours because the game locked up on closing and counted as played for several days multiple times.
DayZ, I have around 3000 hours in it.
Probably League of Legends, I don‘t know how to check how many and don‘t really care, but I‘d be surprised if I hadn‘t spent more than in Rocket League which clocks in at 1100 hours. I don‘t play much of either anymore though. Counterstrike 1.6 is at 400 hours but that‘s gotta be a lie and way more as well lol
I quit a couple years ago for good, but my main account on RuneScape was created in classic as a kid. I had about a year and a half of PLAY time on the account, mind you the vast majority of that was back when you had the hard 5 minute afk timer, so that was at least moderately active play. Then if you add my ironman account I have nearly 1/15th of my whole life logged into RuneScape. I don’t regret it, my whole friend group as an adult stem from those friendships I made online during my young teen years. However, as a modern game as much as I have a place for it in my heart, I found I had more of a negative addictive relationship with it. Maybe I always did, but I didn’t feel a negative mental effect at a young age.
I have over 1k hours in The Long Dark and 7 days to die. Around 500 in space engineers, darkest dungeon, binding of Isaac, enter the gungeon, grim dawn, and satisfactory. ~300 hours in ToME4 and Caves of qud each. That’s just steam stuff though, there are a lot of games that I know are up there that aren’t on steam.
I’m sure I have at least similar numbers to 500-1k if not much higher in Diablo 2-3, and I’m sure more than a few thousand in wow though I lost my og account after wotlk because I forgot the details when I quit so I’m really not sure.
I have over 3K hours on rust on PC. If I include all the hours on Xbox when I was younger it would most likely be either destiny 1+2 or Rianbow Six Siege but Im not sure how to find all that info since alot of R6 was on Smurfs
League of legends, Counter Strike and Warcraft 3 custom maps are waaaay up there.
Factorio is catching up though
steam says I played Fallout 4 for 436 hours, but that seems very high. not sure if that count is accurate.
STALKER and The Elder Scrolls probably hold the record. I may have wasted even more time in my life on World of Warcraft, but I feel like that doesn’t count since you’re just in a fucking trance for several years until you finally break away.
EverQuest was my jam back in the day. It ruined highschool for me. Nearly 5 straight years of farming and raids.
I wouldn’t do anything different though. I met some awesome people that got me through the awkward years of high school when the internet was still somewhat new.
Elite, the original one, on Commodore 64.
Kerbal space program
Old-school RuneScape, 12k hours, another 6k hours on rs3 pre-eoc. Over the course of 21 years.
Talisman
The most that I have proof of is Europa Universalis IV at a little over 1k hours, but I wouldn’t be surprised if my time on Guitar Hero 3 in high school surpassed that by quite a bit. I played a lot of Guitar Hero in high school…