The Early Bird Catches the Worm
–The early bird catches the worm.
This quote perfectly described the current situation. If the Kitsun Lord's army had been ordered to attack a few seconds earlier, they might have been able to prevent the worst-case scenario.
However, since they didn't move to interfere with Mika's attack, the heirloom arrow's power came to full display. It destroyed the southern wall, killed thousands of Kitsun, and injured just as many.
Mika was the early bird and he caught the worm before the Kitsun could do anything.
Unfortunately, Mika was rendered incapable of continuing to fight. He used one of his few heirloom arrows before using every bit of power inside his body to kill as many enemies as possible. Therefore, Mika ended up utterly exhausted and unable to move now that he achieved his goal.