Master Form is a Drive Form which appears in Kingdom Hearts II and Kingdom Hearts II Final Mix. It uses both of your party members, and consumes four of Sora's Drive Bars. It represents the fusion of Valor Form and Wisdom Form, and is obtained when Sora reunites with King Mickey at Hollow Bastion.
Master Form is the third drive form to be obtained, after Valor and Wisdom Form. Subsequently, it acts like somewhat of a hybrid between the two, with a focus on both magic and strength. When in this form, Sora wields two Keyblades and his magic skills are strengthened: the use of magic becomes endless, allowing you to add magical attacks into combos without reducing the amount of physical attacks you can do, more than doubling the amount of attacks that can be input before the ending combo. Master Form is very good for aerial combat, supported by its higher-than-average jump, the Aerial Dodge ability, and movements that allow Sora to stay longer in the air. In Master Form, Sora's running and jumping speed are 25% higher than normal, his jump height is 150% and a second jump is possible while in the air, and his maximum midair combo length increases by 2. [Source: wikia]
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