Blue demon (2)

The Cerulean bird moved, its wings carving through the air with frightening speed. Erik barely had time to reinforce his barriers before the creature's attack hit him—not with its full strength, but with enough force to make him understand the difference in power.

A wall of compressed air slammed into Erik. 

The attack was like a freight train made of pure air—a roaring, howling mass of compressed air that created a thunderous sound as it tore through the sky, akin to a bomb exploding.

The noise was so loud that it hurt Erik and shook his whole body, and he could feel it rumbling through his bones despite wearing armor.

Even with the Absolute Castle brain crystal power at full strength, the impact sent him tumbling backward through the sky.