The two demons attacked with a fury, determined to not let one of the heroes get close to their goal. Swords drawn, alerted to danger long before Zentarou had shattered the door, they struck first.
One lunged forward towards Kuja, one of those clearly a pure caster. He swung with his sword, thinking he could get a quick kill. But Kuja was no novice to battle with melee fighters, and jumped backwards, dodging nimbly even as a spell was springing to his lips.
The second demon went after Vivi. However, in doing so, he passed by Dregan, who took advantage of the move to strike. Thorn dug into the beast's blackened skin, and he howled in pain, but still struck at Vivi. Vivi barely dodged, and was indeed clipped by the blade, sent tumbling with a gash upon his shoulder.
"Don't use area spells!" he cried out. "You'll end up hitting Cal." Dregan went after one, Zidane and Zentarou advanced on another, and the remaining casters fired off spells when they were able. Garnet found her healing magic was indeed much needed, as these demons were more powerful than anything they'd seen yet.
One lunged forward at Dregan and simply barreled into him, knocking the Dunedi to the ground where he fell to biting and clawing. Dregan had no choice but to curl up to protect the more vulnerable places on his neck, and face, and stomach.
"Dregan!" Zentarou quickly used Life Aura to surround the elf in a protective bubble, and tossing the demon away in the process. Dregan scrambled to his feet, scooping up Thorn again, and was casting the instant the dome dropped , reaching out towards the demon.
"Horrid Wilting!" he cried, and the demon shrieked as some of the moisture was evaporated from his body.
"Vivi!" Zentarou shouted, "use Blizzaga after I cast!" Zentarou unleashed a variant on a normal spell, turning a tidal wave of water into a pillar of water, slamming down on the demon they faced. Vivi nodded, understanding, and used the icy spell. As was their nature, the extreme cold froze the water solid, trapping one demon within. That is, until Zidane hit it with Thievery, causing the ice to crack and break and spilling the injured demon out onto the floor.
"Try to trap one!" Kuja abruptly called out, dodging as the demon struggled to his feel and unleashed a wave of molten lava at his enemies. "They'll know who's behind all of this!"
"Right! Brothers! All cast together, ice!" All the Bretheren Arcanum, and Kuja, simultaneously casted their most powerful ice spell at one demon, and although Vivi and Kuja's were area attacks, Blizzaga, the combined effect successfully froze one demon in place in a small glacier. He wouldn't be going anywhere anytime soon.
Now, there was only one demon left to deal with.
Sensing victory, the heroes unleashed their all upon the unfortunate demon, spells and steel seeming to explode upon it from every direction. Within minutes the demon vanished.
"Vivi, hurry!" Dregan gasped, dropping to a knee, blood oozing from various wounds. Without hesitation, Vivi darted to his son's side and jerked out the needles and removed the dome. The tubes were still half-filled with the fluid, which began to drip onto the flood. Instantly Cal's struggling ceased, and he went still, eyes closed and breathing ragged.
"Cal, Cal, please, open your eyes," Vivi begged. "Please answer me, let me know you're okay."
Meanwhile, Dregan, receiving a little healing from Garnet, was approaching the demon.
"Now, lets see what you know." He reached out a hand lined with fire to melt some of the ice, but a startled cry from Vivi, closely followed by a wave of sonic energy, interrupted any such thoughts and threw everyone to the ground. The ice around the demon shattered, and the beast, very nearly mortally wounded, tumbled to the floor. But he was laughing weakly, as all looked towards the source of the assault.
"You fools!" he sneered. "You interrupted the final stage! You have no idea what you have done!"
Vivi was sprawled upon the floor, one arm slightly upraised, looking in shock at Calan, who was standing.
"We were in the process of changing him from an obedient son, to an obedient slave, and you stopped the change before it could be completed!"
Calan slowly looked up from his father on the floor, to the others, and his normally yellow eyes were glowing with a reddish light.
"There is only one state between the two, and that is wild, chaotic, berserker rage! He will kill us all!"
Calan raised his hand, and unleashed a powerful waterga spell. The demon wailed, and didn't disappear. This went beyond normal banishment. The demon turned to powder before their very eyes.
Then Calan, oldest of the Black Mage children, turned on those sent to save him.