Lacking on storytelling
After few hours into the game, I thought it was not as bad as the consensus claimed it to be. I mean, sure, the writing hit me first as terrible and never managed to rise above acceptable. The plot was not interesting and I regularly had trouble suspending my disbelief. Doug Cockle's glorious raspy voice does not fit the looks of the protagonist, Eric Bane (why does it sound so damn cheesy?), at all. I was always half expecting Eric to introduce himself as "Geralt of Rivia. Witcher."
The obvious lack of well-established lore hurts the story too. From the looks of the Sanctuary night club I can tell the developers have played Vampire: The Masquerade -- Bloodlines. Too bad Realmforge Studios did not have White Wolf's World of Darkness license to draw lore from like Troika had. Feeble are the attempts to create a similar atmosphere in Dark.
Gameplay seemed fine
Shadow Kill was more to my liking even though it requires one Blood to use. The ability teleports you to an enemy to take them down -- like Mass Effect's Biotic Charge, really -- and its last upgrade makes it stun other enemies in vicinity. Which makes the ability a must-have for killing two enemies that are facing each other if you do no want to alert anyone. Another of the eight active abilities I mostly used was Shadow Grip that kills an enemy from a range, and even disposes the body when fully upgraded.
There is also a passive ability, bit like in Alpha Protocol, which keeps you unnoticed for a short while in enemy's sights. But I think I prefer the three levels of alarm games like Deus Ex: Human Revolution and Dishonored have. The first level is when an enemy catches a glimpse of you and stops their routine to stare at the spot for a while. On second level they see enough to come to investigate. And on third they identify you and go hostile. I think that kind of system is more immersive, even if the mercy timer is explained in Dark by vampires being harder to spot.
At about four-hour mark I started to see the problems with the game. Every map has a ridiculous number of enemies. It takes quite awhile to plan your way to take down them all without being seeing. And often the areas get refilled on your way back. A stealth perfectionist like me certainly wants to kill them all, especially due to them giving experience for upgrading abilities. It is tedious and very monotonous, too, since there is no variation to the gameplay. The only thing you can do besides sneaking and taking out enemies, is finding PDAs which give 2.5 unalarmed enemies worth of experience each.
I had to turn down the difficulty from Normal to Easy soon after the gameplay had lost its charm. This was because in Dark, the difficulty setting determines how many times you can save between checkpoints. On Hard, you cannot save manually at all. On Normal you get 2 saves, and on Easy you can quick save as much as you want, which is what it should be. Mere 2 saves resulted me replaying parts way too often after being noticed and ruining my perfect run.
Straight up combat in Dark is not terribly enjoyable. Killing alerted enemies is more difficult. Armored ones even block your takedown attempts from the front. And restoring your Blood by sucking enemies does not work if there is even one additional enemy there.
The first two bosses were kind of all right for a stealth game but the last one is something else. He merely jumps around the arena while you avoid the highlighted target areas and activate terminals. All the while your vampire friend, Rose, keeps repeating the same line. After the "fight" is over, you -- for whatever reason -- get a choice for which ending to go. I do not believe there was really need for that.