THE DARK MOD was once a total conversion of Doom 3, and is now a STANDALONE GAME with the release of TDM 2.0! A dark and moody stealth game, inspired by the Thief series by Looking Glass Studios.
Very good stealth mechanics, seems to be a decent toolkit though I haven't spent much time making missions yet. Keep in mind that this mod is mostly just a toolkit, and relies on user made missions.
My main problem is with the melee combat: the concept behind it is great, but it's executed poorly. Basically, you press LMB by default to swing a melee weapon, and MMB by default to block/parry. However, there are four different types of swings and four different types of parries; each parry blocks one type of swing from an enemy.
Cool in concept, but it's ruined by the controls which don't seem to be changeable for this. The type of swing or parry you do depends on mouse movement: moving it to the left does one type of swing or parry, to the right does another, and up and down do others. This is awful since the mouse is also used for looking, it shouldn't be used for both. It's so common to do the wrong type of parry and die as a result, because this control scheme is terrible.
What should have been done was; rather than using the mouse to determine which type of swing/parry to use, you should use the WASD keys instead. Common sense suggests this is a better method, and it has been proven to work very well already. Try out Cryostasis: Sleep of Reason to see this utilized properly. Morrowind also uses it, though the combat in that game is too flawed to begin with. Still, this is a necessary change that should be done in the future. It's not too big of a deal though, since this is a stealth mod. Just don't be spotted, and used ranged weapons if you do.