Here is the "Gordian Quest" formula:

• take the best of Darkest Dungeon and the best of King's Bounty and fuse them;
• add some good D&D & "Game-book" elements;
• add the best camping system ever made;
• add the best hero development ever made (you have 10 heroes to pick for your parties, and you can literally build your skill grids);
• add tons of different enemies (included 15 unique Bosses), wonderful items & funny combat cards (most of them active, and in rare cases passive skills);
• merge all these elements in an excellent way ...

to get one of the best games ever. About the game lenght, the main Campaign alone (at minimum difficulty "Hard") is around 80 hours if you are a completionist like me. And the game offers a lot of post-game contents (special arena & dungeons for the main Campaign characters + "Realm mode").My final rank = 10/10.