"Boom, boom, boom...!"
Terrifying explosions merged into an unbroken roar. Outside Black Iron City's gate tower, shattered iron and scorched earth flew everywhere, severed limbs and arms hurtled through the air, and agonized screams rose from every direction.
The row of black cylinders atop the gate tower spat fire serpents without pause, unleashing dozens of thick fire serpents at a time.
Almost less than a breath later, the next volley came.
Twenty black cylinders fired in alternating volleys, keeping at least a thousand fire serpents streaming through the air at any moment, blasting into the allied forces with terrifying destructive force.
The cultivators of the Three Sects were blasted off their feet, flesh and blood flying everywhere. In an instant, swathes of them were killed or wounded.
By now, the leaders of the Three Sects, watching and overseeing the battle from the rear, were already staring wide-eyed in shock.
Fan Chengji cried out involuntarily.
"These... these are Thunderfire Divine Mechanism Crossbows!"
The three sects of the Southwestern Borderlands each had their own strengths.
Among them, the Iron Halberd Gate excelled at artifact refining, and the Scarlet Fire Heavy Crossbow was their masterpiece.
As an artifact refiner, Fan Chengji immediately thought of this renowned "Killing Weapon" when he saw the dozens of black cylinders atop the gate tower madly spewing fire serpents.
Unlike the Scarlet Fire Heavy Crossbow, which was merely a spirit artifact enhanced with a little Spirit Power, these were different.
The Thunderfire Divine Mechanism Crossbow was a genuine low-grade Saint Weapon.
Not only did it deliver a terrifying impact of Spirit Power, but paired with the powerful explosive force of Divine Mechanism Crossbow Bolts, its destructive power was several times greater than that of a Scarlet Fire Heavy Crossbow.
Even more terrifying was the Thunderfire Divine Mechanism Crossbow's