It required an explosion, which was the difficulty of the trick. If the explosion were too weak, the cannon would be useless. If it were too strong, the cannon itself would burst apart. He and Axiolis had to strike the correct balance between power and structural integrity.
Zeff plugged up the cannon and filled it with warm, swirling water. The time was ticking now, because the surrounding ice would freeze the water if he took too long, but Zeff knew the timing. From there, two things needed to happen in near succession. First, he had to create a vein of superheated steam inside the sloshing water. The heat would cause the water to boil in a violent flash, resulting in the explosion he needed. Second, he needed to materialize the soul-strengthened cannonball with his maximized velocity. This way, the explosive velocity of the steam would increase the already moving cannonball, granting it much greater punch than Zeff could give it otherwise. And it all had to be done in an instant, with immense precision.
With full concentration, Zeff wrenched one open palm upward and created the vein of superheated steam, and with the other hand, this one a closed fist, he threw a backhanded punch, creating the cannonball of solid ice while simultaneously unplugging the cannon.
The cannon jumped from the force of the explosion, and the cannonball rocketed into the sky and barreled into the Gargoyle’s stomach, shattering on impact.
And Sanko hardly even seemed to notice.
Zeff scowled inside his own mind and just kept firing. He’d hardly expected it to end the fight, but still, this was more than a little frustrating. His ice became all but lost in the huge flurry of other attacks that the Rainlords were launching. Multiple paths of destruction, little more than splinters against the Gargoyle’s skin. Octavia’s singularities managed to poke bigger holes into her, but they didn’t seem to be doing very much.
Then the Gargoyle finally launched an attack of her own.
Earthen spires shot out of the giant’s body in every direction--thousands of car-sized arrows looking for Rainlord blood. And finding it, too, because Sanko also chose that moment to send an earthquake tearing through the ground, throwing everyone off balance.
Zeff tried to avoid them by leaping off his platform, but one spire took his head clean off, along with his arms and chest.