Maybe the question has already been asked before, but...

Mines are:

1) Dofus. A game that a first glance may seem childish but it's very tactical and deep.
or maybe
1) The Championship/Football Manager serie (now i've stopped playing because it become worse every new year).

3) World of Warcraft (now i've stopped playing because it become worse every new year)
or maybe
3) the Civilization serie.

5) Maybe Path of Exile, Fallout serie, Borderlands serie or Close Combat serie.

What yours?

I think Pirate King is a pretty cool One Piece game. The game become better every updates. you can try to play this game. JoyGames.me

Fallout New Vegas.
Tales of Majeyal
Underrail
Wizardry series games
Ultima series games
Might and Magic series games
Heroes of Might and Magic series games
Age of Wonders
Age of Empires (I and II, III is shit)

More time than what?

Playing games increases your lifespan...?

The Governor called. I'm afraid he denied your petition. You go to the gallows tonight.


NO! I need more time! Let me play Fallout!

List is very long.
But I can mention few names
[PROTOTYPE] I have played it 2-3 times completely!!!
Risk of Rain 1200+ hrs
System Shock
DOOM and it's mod
Quake and it's mod
Shadowgate
Steamworld Dig
and few more...

Final Fantasy I
Final Fantasy II (somewhat)
Final Fantasy VI
The Spyro series
The Crash Bandicoot series
Sonic 1
Sonic 4 Episode II
Sonic Adventure DX
Minecraft (all the freaking time, Java, Windows 10 Edition and PE on Android)
VVVVVV
Super Hexagon

Those are off the top of my head.

Ragnarok Online: I'd say I've spent most of my gaming life there. Discovered the game when I was 16 or so and I have 25.
Final Fantasy X: 3, maybe 4 full runs.
Final Fantasy XII: ^
Skyrim: around 400 hours or so.
Final Fantasy XIV: I only played for two months, but got way more hours than Skyrim out of that period of time. If I had a steady income to pay subscription, I'd say I would have turned the 3-4k hours long time ago.
Star Ocean games.

The single game I've spent the most time playing? Tough one :P Perhaps Warcraft 3, Fallout 2 or Civilization 4.
Terraria is quickly catching up though

Doom comes first, no question.

Second could be Deus Ex. Or Age of Empires.

Dota 2

Clash of Clans

Romance of the Three Kingdoms series

Football Manager series

The game I have played most is without a doubt Neverwinter Nights, played that and Baldur's Gate series for two years. I didn't play anything else during that time.

OOTP Baseball.

No, penis. Mine is already longer than my nose, then again they both seem to grow for some reason...

As for games to which I've wasted too many hours of my life which I'll never get back, Team Fortress series of multiplayer shooters wins easily. Quake TeamFortress, Quake MegaTF, Team Fortress (Classic), and now Team Fortress 2.

Oddly, I've never really invested any time to any other online multiplayer games, I've always found other online games boring and uninteresting, even Counterstrike or Crysis 3. Even before I tried out the original Quake TeamFortress, I tried some other Quake multiplayer games (deathmatch, team deathmatch (where you collected skulls of enemies to bring to some place for extra points) etc., but they also bored me quite fast. But TF, somehow it just clicked, and has kept doing that ever since.

I've also tried some other genres online like Diablo (2?) co-op or some RTS, but meh.

So if the TeamFortress series ever dies, I guess that'll be the end of my online gaming. Oh well.