Lands of Erdos
Invisible and intangible matter that is believed to permeate the universe. In its excited form it is visible and highly toxic.
Invisible and intangible, magis surrounds the multiverse. In its natural state, it is inert, harmless, and seemingly useless, save perhaps as a part of a cosmic equilibrium too unfathomable to mortals.
Excited magis however, is another matter entirely. Toxic and dangerous, it appears as a glowing, billowing smoke of shifting colors. But it is malleable and with training—or divine gift, or innate ability—magis can be manipulated to produce wonders.
This is not an art, it is a science. And it is called magic.