One week later:
Rivers of lava were brightly glowing as they flowed through the valley. Everything was submerged under the darkness brought by the sky filled with thick clouds and pitch-black smoke, the only light source being the rivers of lava and occasional electrical sparks.
A mountain-sized mass of metal, crystals and dark, stone-like material was lying without moving, as if it was a real mountain. It was a giant dragon, resting with his tail curled around his body.
The dragon was staring at a small floating book before him, the pages flipping one by one at an insane speed, the dragon's eyes looking almost blurry as he read through the lines with a speed of a machine.
'So, this is how it works!' Vesuvius quickly cross-referenced the knowledge contained within his inherited memory and the book's contents. His intelligence stat and brain evolved for magic processing the data with the speed of a supercomputer.