Roy's claw scratched one of César's eyes, which also made Roy aware of César's weakness.
Just as Roy was about to seize the opportunity and follow up to destroy César's other illusion demon eye, the large mouth on César's abdomen opened wide and spat out a green mist with a strong smell at Roy.
Roy blocked with the frost shield in his hand but found that the mist did not seem to be formed by magic power. The Magic Power Virus on the shield did not react to it, but rather, the mist was corroding Roy's shield.
Seeing this, Roy knew he could not let this green mist touch him, so he flapped his wings and flew back.
This thing seemed to be César's stomach acid. After the mist touched the ground, the corrosion became stronger, and even thick smoke rose from the ground.
