Boom! Boom!
From behind enemy lines, a series of booming cannon blasts resounded. The projectiles shot toward the city barrier, and once they hit—
Boom! Boom!
Explosions roared as the projectiles struck the barrier, creating ripples across its surface. The lightning cannon on the flying fortress began recharging, crackling with energy once more. Though a crack had formed in its structure, it could still fire a lightning beam—albeit at the cost of further damaging its front section.
Baron Rosalind simply let the cannons strike the barrier; at the very least, he had already blocked one of the lightning cannon's attacks. Based on his earlier estimation, the flying fortress would need three shots of its lightning beam to break through the barrier.
Though he didn't know exactly how many energy stones the crew had brought aboard, he guessed they had no more than enough for three full-power shots.
