Mana Zone is a skill that allows a mage to manipulate the mana in an area around themselves. Thus, the mage can gather together and utilize more magic than they would be able to normally.
Offensively, this mana can be funneled into spells to increase their size, number, and range. It can also be used to launch attacks in any direction and from any direction within the zone. Spells can be created all-around a target to keep them from escaping, within an enemy's spell to destroy it, or behind a target to catch them by surprise.
Defensively, the mana can be used to sharpen mana-detection and heighten reaction time, as well as to augment Mana Skin and other Reinforcement Magic spells, allowing for the prediction of enemies' attacks, as well as allowing the user to move and stand in mid-air.