Darkest Dungeon -- early access
So far so fun. I reaaaaally dig the writing in this game. It's your Diablo-esque gothic dialed up to absurdity, which is precisely the sweetspot for that sort of writing as far as I'm concerned.
Game mechanics are engaging enough so far, you get your bunch of heroes and go on adventuring and they become afflicted with various crap from stress in the dungeons, so you meditate, drink, pray, flagellate, gamble and whore them until they are ready to go back in. They gain XP, loot and upgrades to take on bigger challenges, and you keep turning the crank. Very satisfying.