It took ten points of Mana per second to sustain the Storm Eagle, which meant that 36,000 points of Mana would've been consumed within an hour. Link's current maximum Mana limit was 5200 points, but because of the series of attacks he unleashed earlier, he was now left with only about 2400 points of Mana.
In other words, if he were to keep on maintaining the Storm Eagle in the air, he'd be completely depleted of Mana in less than four minutes. The Mana consumption rate of a high-level flying spell was simply astronomical. This was one of the crucial reasons why flying spells weren't the most practical spells to use in battles.
Fortunately, though, Link had come up with a way to deal with the magic puppet Nana.
Link made the Storm Eagle climb higher up into the sky.
"How much time do you need to cast Metal Decay?" Link turned around to ask Vance.
