Civilization. Dumped thousands of hours into multiple entries in the series.
Minecraft. Probably the most hours I have in a single, specific game, with a splash of the category below.
Modding. I've got thousands of hours in New Vegas, Oblivion, Skyrim, and Fallout 4. Most of those hours are messing around with mods.
After that it's League of Legends, which I've got about 4,000 matches logged in, though I haven't played much in the last few years.
Another rung down from there are the other competitive online games I've played: Magic the Gathering: Arena and Street Fighter V, most prominently.
Then the MMORGPs (FFXIV, WoW, and FFXI), though I've been off that particular trolley for close to a decade at this point.
After that it's the roguelikes; nowhere near the same level as the MMOs or competitive service games, but I've still got quite a bit of time put into games like Darkest Dungeon, FTL, Hades, etc.
Next step down from there is Souls games, with NG+7 or higher in all of them but DS2.
After that? I guess probably the sprawling 40+ hour single-player RPGs, vying with high-replayability action games (DMC series, Bayonetta, Resident Evil, etc.). I usually play them to (post-)completion and a bit more on top.
Bottom of the rung, easily, is single-player narrative experience games. I played Uncharted, but I didn't played it for more than an afternoon or two.