"Hundreds of hours" is almost impossible without fomo or mods and most of the time they are f2p games but sp b2p games with longer length than usual are: Factorio, Total Warhammer trilogy, Civilization IV-V-VI, Stalker trilogy (fuck 2), Anno 1800 with dlcs, Call to Arms with dlcs, Sins of a Solar Empire I with dlcs (can be unlocked through Creamapi so don't buy them), Killing Floor 1+2, Deep Rock Galactic, Path of Exile 2, Yakuza series, Witcher trilogy, Xcom series, Dawn of War 1+2, Kingdom Come Deliverance (ignore woke 2), Halo Master Chief Collection (just beating campaigns and playing a bit of mp resulted in over 60h), MH Rise, Tropico 6, Planet Zoo