Asklemmy

Path of Exile. It literally captures you once you take a grasp on game mechanics and find an interesting character build.

Oh boy, theres a lot to talk about chatacter building.

Theres no ARPG game in the market with such complexity in planning your character. Dopamine hits when you reach your build's peak and while you chase for milestones, like upgrading gear, leveling, bossing, etc. Leagues are breath of fresh air, introducing expansions + new content, also possibility to start a fresh character in fresh ladder & economy.

Playing PoE with pals in a guild and sharing milestones, moments, items & currency, helping each other with progression sucks you even further in.

Its so addictive that I've had to stop playing it, because it takes so much of your time. But I don't regret playing it. Good times.

Easily 10k hours throughout the Diablo series.

That would be Elden Ring. Spent 200+ hours on that game (might sound like rookie numbers but that was my first open world game, was just a casual gamer before that).

Either Sims or Transport tycoon Duluxe

hotline Miami, katana zero, ultra kill.

Either skyrim or oblivion. probably Oblivion. It's the most immersive game world I've encountered. Emminently replayable.

The Elder Scrolls Online

Gtav on ps3 was a blast.

Minecraft. 2.5 kilo hours

Diablo 2 from launch, I won't even guess the hours because it's over 10k easy and that's just not good. Path of Exile says 4k+ hours as well. I'm an old fart though.

Guild Wars 2; I'm at 6-7k hours or so. Been playing a lot less lately; I'm not sure if that's the recent content, or if it's me getting tired of it. I don't have a ton of objectives I'm interested in completing at this point; some "nice to have"s, but at this point any character or build I could possibly want to play, I have just about everything I need for. Mostly find myself logging in twice a week to do guild night with friends, and that's it.

Otherwise, GTA V, which surprises pretty much everyone I know except the friends I play with. It's just such an easy game to spend hoursblowing each other up or racing around or whatever in; really a fantastic game to play with friends.

Probably Planetside 2, an online MMOFPS game.

Next are probably: (Don't know in which order)

FTL: Faster than Light (with Multiverse Mod)

The Elder Scrolls 5: Skyrim

A small multiplayer game called "Red Crucible 2" (browser based FPS game that runs in Unity Plugin, game's now dead)

GTA V

GTA IV

Note: I don't have the times on these games because I might or might not have "downloaded" some of them outside of official stores... so its just based on how vividly I remember them.

Old School RuneScape, by a lot!

I'm over 10k hours on FFXIV, been playing since launch. Could get an exact answer when i get home. Next closest is Skyrim with around 1,500.

Edit: it's over 14k hours, more than 584 days worth. It'd be much more if I had more time the last two years but I can't do much than dailies with a 15 month old!

Pokemon Firered. One of my favorite childhood game.

Call of Duty Modern Warfare

1200 hours on Halo The Master Chief Collection on steam. And absolutely countless more on Halo Reach on the Xbox 360.

1. RDR2 - 2,225 hours
2. MGSV - 1,388 hours
3. TW3 - 645 hours

I'm sure SMW is the real 3rd. place, but I don't have the numbers.

I have 1000+ hours in Forza Horizon 4 & 5, mainly due to weekly FOMO (new car every Thursday).

Quake Champions for sure. Best competitive shooter I've ever played (and I've tried all the popular ones), great option if you like movement & aim centric games

~800 hours into PAYDAY 2

~1800 hours in various sim racing games, assetto corsa, project cars 2, dirt rally/DR2, rFactor2.

And some ~300 hours in Stationeers

EverQuest 1. Diablo 1,2,and 3. Cities skylines. Forgot about terraria.

AOE II was my childhood. I played that game for years.

I would guess I have multiple thousands of hours across the Halo and Pokemon series. My highest played steam game is dead by daylight (gross) at 1k hours. Deep Rock Galactic and PUBG are at around 500.

Breath of the Wild. I put about 300 hours into it.

1. Doom I and II with who knows how many hours since Christmas 1996.

2. Minecraft since 2011.

3. Binding of Issac with close to 1k hours.

4. Factorio with 850+ hours and currently rising.

not really a single game but probably accumulated the most hours playing Super Mario World kaizo romhacks

single game would probably be Battlefield 4 though