CDPR's Magnum Opus. First of all, it is very difficult to write a short version of my thoughts about this masterpiece. I've played games from many genres for more than 10 years, but there has only been a few of them that left marks in my mind like this one. You can find elements of RPG, Action, Adventure, Drama, Suspense and whatnot while experiencing its world. In your first run, you will probably spend around 100 hours by enjoying side quests which are not like ones we commonly see in other games. I strongly recommend GOTY version since it contains DLCs that should not be overlooked. A lot of companies would have made standalone games from both of them, so this should give you an idea about how long it will take to complete the whole game.