Mana is perhaps the greatest element-force in the universe. It provides and sustains life. Without it, life would fizzle away. Nearly every planet has an abundance of mana that helps grant its inhabitants longevity.
Mana is also the fuel source for magic, the way which ideas are brought into reality. Magic is nearly impossible without a sufficient source of mana.
This sticky, gooey substance found throughout the air and in living things is the balancing force to aura.