In a nutshell, Dark Fantasy is a form of Setting Aesthetics where a standard fantasy setting is portrayed in darker and edgier ways, usually with whole-hearted embracing of grimdark. Whilst it is sometimes overlapped with Low Fantasy, this does not have to be the case; High Fantasy trimmings such as abundant magic or plentiful non-human races can be used in Dark Fantasy, it is merely the grimdark light that they are presented in that defines this setting - Warhammer Fantasy is, when looked at from the angle of its wargame, a Dark High Fantasy setting (although the Warhammer RPG, inversely, presents its as more of a Dark Low Fantasy).
Common trappings of Dark Fantasy include:
- Magic is at best a neutral and easily abused force, at worst it's an actively evil force and often corrupts or destroys those who wield it.
- "Darker" forms of magic, such as Blood Magic and Necromancy, tend to be much more common than benevolent magics, such as healing.
- Magical weapons will often require a price in exchange for their power, exacted from either the bearer or the bearer's allies.
- The wilderness is actively malevolent, with the (often horribly deformed or unnatural) beasts and monstrosities seeking the destruction of humanity.
- Civilization is an utter shithole, where the powerful crush and debase the weak.
- At best, "heroes" are closer to anti-heroes. At worst, you've got a case of self-centered assholes who'd normally be the villains being presented as "heroes" because they're at least fighting the forces seeking to make the world even worse.
- The gods are apathetic, viciously cruel, or non-existent.
- The church(es) is (are) corrupt, power-hungry, or actively evil.
- The world is truly bleak and any victories you win are ultimately pushing back the inevitable destruction of the world, and your efforts are pointless in the long run.