Does "realistically detailed" mean that is has to have Fire Brands, Charcoal Shields, Vinemen, winged mages, red-skinned warriors whose mere touch will burn you, Moose Riders, etc etc?
Have you ever tried playing a roguelike? Linley's Dungeon Crawl is very good, and I have actually managed to beat ADoM once. There's enough challenge in both to occupy one for weeks, months or years.