The magic systemMagic is literacy
Here, magic has rules, and the rules make the story.
In Varnur, almost everyone uses some magic. Nine in ten people know the basics of at least one school, learned as life demanded it. And no one is entirely defenseless. When faced with death, anyone's body will thicken the air around it into a defensive barrier on its own. This happens across all races, even to people who have never studied magic and cannot explain what their body is doing. Raising that barrier deliberately requires training in Wind magic.
Magic is common. Mastery is rare.
Two paths of study. Level measures a mage's control over their own mana: beginners need gestures and words, experienced mages need only will it, and the rare few at the top draw on the mana in the air as well as their own. Form measures how well they know a school: first they control what already exists, then they create, then they master its most demanding techniques, until they command everything known to be possible with that matter.
The schools. Water, Earth, Fire, Wind and Light. Transmutation, Summoning, Enchantment and Molecular. Alongside them are Body Reinforcement and Object Reinforcement.
Magic follows physics. Each school works on real matter, and that matter behaves as it would in the real world. Combining elements yields what physics and chemistry would: water and fire controlled together make ice; fire and earth make lava.
Magic comes from imagination. A school defines what is possible; the shape, the glow and the way a spell is cast grow out of the caster's life. Two people at the same stage in the same school may reach the same effect by very different paths.
All magic has a price. Every effect costs mana. A mage can exhaust their reserves or injure themselves by channeling more mana than their body can handle.
No one is made of steel. Reinforcing the body has a limit, and there is no magical healing. Even a great mage must live with their wounds. In Varnur, almost anyone can bring down almost anyone.