I really like Darkest Dungeon. I like the art direction, the JRPG-inspired gameplay, the dungeoncrawling and the “adventure” being divided into different phases of play (which some say reminds them of Torchbearer).
Before going all-in though and scaring my rules-light-loving friends away, I only tried to implement two mechanics from the game, to see if and how they would work: stress and torches.
The stress mechanic was something I blatantly ripped off from a game I played with @glocke where my character Dr. Robert Glancy, a chain-smoking FBI-psychologist, nearly died of a heart attack.
The torch mechanic was something I wanted to test, to see how easy it would be to integrate some light (pun intended) ressource management into the game. Playing in turns is crucial for this mechanic to work as smoothly as it did.
Stress-mechanic
The TARGET equals the player’s stress. The TARGET starts at 10. Whenever a player gets into a stressful situation, they roll a CHA-check vs. TARGET. If they fail they raise the target by a certain number (sometimes 1 point, sometimes more depending on what caused the stress). Calming yourself down to reduce stress and thereby the target, takes a WIS-roll against the TARGET to “heal” stress by WIS+1 with 10 being the baseline.
Torch-mechanic
Dungeons are dark and torches are needed to see and not suffer stress.
1 inventory slot = 5 torches. A player has to spend 1 action to light a torch, which lasts for D6 rounds (I was thinking of only making it D4, but D6 makes more sense, because I understand torches as TOOLS). Every turn a torch is not lit, every player suffers 1 stress (raising their TARGET).
Darkest Dungeon lends itself to a Dungeoncrawl quite well, I think, so prep is really easy, because you can plan your “dungeon rooms” as separate scenes with stuff in them that player’s can interact with.
Instead of planning encounters, I just prep monsters and decide for every scene if there are monsters or not (by rolling the skull dice; skull = monsters, no skull = no monsters). If you borrow the structure of The Grind from Torchbearer you can even have a “town phase” (stocking up on torches, weapons, rations etc.), a “dungeon phase” (exploring, fighting, looting) and a “camp phase” (where players can rest, eat, regenerate HP or stress). If you wanted to make the game crunchier, you could integrate mechanics for rations (5 rations = 1 inventory slot, eat 1 ration after 6 rounds or something like that), rules and feats for camping and expand on the stress mechanics by giving players quirks as a result of reaching 20 stress.
Anyway: I did some Darkest Dungeon monsters using the TIER-system in ICME, which I wanted to share with you. Since this post is already very long, I am going to do a separate post that only contains tokens and stats for the monsters I threw at my players. Thanks for reading and take care, all! 
