An MMO called Mabinogi, but only because it's literally designed to suck as much time and money away from you as possible without you noticing. Steam says I'm nearing 5,000 hours, but more than half my playtime was from before it was on steam, so it's probably closer to 12,000 to 13,000 hours. I haven't even reached the end game yet.

At this point, I don't really play it anymore. I think from now on I need to start avoiding games that are gonna absorb that much of my time for so little progress. Definitely wasn't mentally healthy because I wasn't even enjoying myself a good way in, I was just addicted.

Various versions of The Binding Of Isaac

Kerbal Space Program

Diablo 2. Heroes of Might & Magic 3 coming next.

I might have more hours @ World of Warcraft, but that's outright drug and wasn't played for most of time voluntarily.

Please send help.

This is actually a good question if I'm answering it entirely based on feels, not actual data.

Biggest game overall, single player plus multiplayer? Halo series. Maybe Destiny 1&2 too.
Biggest PC game? Probably Neverwinter Nights (2002). (This predated Steam, so fuck the statistics anyway.)
Biggest game I'm spending shitloads of time right now? TRAIN SIM WORLD 3.

About 1200 hours in Destiny 2. My wife and I have about 2000 hours combined in Destiny 2.

I'm afraid to find out how much time I've spent playing League of Legends. Unfortunately the Time Wasted On website only goes back so far, so my stats aren't accurate.

According to Steam:

Monster Hunter Rise, 754 hours

Back 4 Blood, 616 hours

Monster Hunter: World, 581 hours

Cyberpunk 2077, 470 hours

Hitman 3, 288 hours

Rocket League has to be at the top along with Forza. Driving aimlessly without burning fuel in scenic views takes the chart

Honestly? Skyrim. Played it a few times on different platforms. Different builds, different experiences.

Deep Rock Galactic at around 300h

According to Steam, Arma 3. But I know for a fact that a lot of those hours were not technically in game because I would spent hours upon hours in Notepad++ scripting for my modules while I had the in-game editor running in the background to alt-tab in an test things every now and then.

TF2 is second, and that's all actual play time, baby.

However, in Ultima Online I spent a good 8+ hours a day, every day, from 1997 to 2003. So probably that; I just have no actual counter for the time put in.

Tarkov. They shit sucked me dry. 1500

Binding of Isaac, over 1170 hrs.

Have I seen everything or am I any good at it? Hell no.

No Man's Sky. I think I'm around 800 hours on that one

FFXIV with over 5k hours.

Team Fortress 2. About 3000 hours and I haven't played it in years, I was addicted.

I must say, there are a surprising amount of factorio players on this threat, glad to see that!

Hard to say, I've been on an OpenTTD (since Transport Tycoon), Dwarf Fortress (since .31), Minecraft (since Tekkit) and Factorio (since .11) loop for several decades now, with 1000s of hours in each. I tend to play one at a time, currently doing Enigmatica 6 Expert.

Rimworld, KSP1, Stellaris

Easily Rocket League. I think I’m somewhere around 2,000 hours at the moment.

Tabletop Simulator. In 2020 my weekly gaming group couldn’t meet anymore, until we discovered that solution. We still meet in person occasionally but we have been playing every week online. I’m genuinely not sure how I would have gotten through the lockdowns without it.

ooh, astroneer is great! haven't played it myself but seen some gameplay of it. mine is Planetside 2 with about 2400 hours... most of that is from the past two years I'd say

Elder Scrolls Online, by far

War Thunder. Well over 2000 hours across two platforms. I regret every minute and every penny spent.

Kind of difficult since aside steam I have no clue on how many hours I have spent, especially for console games.

That aside, my most played game in steam are:

• melvor idle with 1500 hours (it's an idle to be fair, kind of runescape but it's only a UI, you leave it open farming)
• factorio at 700 hours (the entirety of the factory building genre is pure crack)
• risk of rain 2 at 400 hours (it's the perfect sequel and a damn fun roguelike where you stack items until your pc breaks)

Stellaris

I probably have years of playtime on Super Smash Bros. Melee for Nintendo GameCube

Before the community died off I had put just under 20,000 hours into Subspace / Continuum (mostly on EG). No, that's not a typo. I learned what addiction looks like as I grew older.

Between that, NexusTK, The Realm and an unhealthy obsession with SNES JRPGs I don't know how I managed to make it through grade / high school...

If we count map editors then most likely C&C: Generals: Zero Hour or ARMA 3.

If we don't could editors then probably Halo 3 or MW2, maybe Stellaris.

Minecraft Factorio EVE: Online Cs:go LoL

Dead By Daylight has consumed more of my life than any other game at 1600 hours (since 2018), and that’s still rookie territory. I’ve never been able to commit to a game for very long, maybe 40-80 hours max and that was only two or three games in my life. DBD just has a hold on me.

Risk of Rain 2, man. My absolute favorite game of all time.