What always gets me about jinn mythology in fantasy novels is how much it diverges from the 'wish-granting genie' stereotype. Authors pulling from the rich tapestry of pre-Islamic Arabian and later Islamic lore often create magic systems that are fundamentally about contracts, binding, and true names. The power isn't just a spell you cast; it's a negotiation, often with a willful, alien intelligence that operates on a logic totally separate from human morality. It makes magic feel less like a tool and more like dealing with a force of nature that can argue back.
You see this in books like S.A. Chakraborty's 'City of Brass' trilogy, where the Daevabad jinn are divided into elemental tribes, their magic intrinsically tied to fire, water, earth, and air. Their society, politics, and even their physical forms are shaped by this elemental essence. It's not just 'magic'—it's biology, culture, and history all rolled into one, which makes for a deeply immersive system where the magic feels like a natural part of the world, not just a plot device bolted on.