Aura Barrier

Eiro looked at his slightly glittering right hand. The light that was created through Lognir's magic to keep the place lit up, as well as the flames from Armodeus' forge, were reflecting off of the metal insets that were placed into Eiro's prosthetic. 

Right now, he was trying to test out the full 'Frost' set that was created with the metal that Armodeus pulled out of the Frost Dragon child's egg.

Switching out part of his index finger was already potent enough, but with his whole hand, the effect was at a whole other level. The power of other sorts of magic were considerably weakened, while ice magic was strengthened by quite a bit. And of course, Eiro was mainly testing this out through freezing water and lowering the temperature of the air, since casting full-on magic would be a bit reckless in a cave such as this.