Probably most hours I've spend where with Conquer Online back in the days before mysteryboxes where introduced. After that probably puzzle and dragons.

Luckily after those games I learned to question my time spent in these games. (Basically just one day after grinding tower of gods for umpteenth time to spend my 1k stamina/energy, I asked myself wtf am I doing with my life, was I having fun?)

After that my most played games have been Grim dawn, Sacred2, Monster hunter world, No Man sky, Incredible adventures of van helsing then various 2d fighters like Blazblue, undernight inbirth and Granblue fantasy versus that I play on locals.