Raw magic is the lifeblood of the planet. It builds and flows across the surface, and through the substance of the world. Concentrations can form Genius Loci, arcs between loci form ley lines from which powerful energies can be tapped.
Magi are tuned to the fluctuations in the aether, and can use the imbalances to power their arcane spells. As they advance in the ways of magic, they can channel greater energies.