Of course, the levitation magic rune was merely an example Angel had given. The magic rune actually inscribed on the wall was not a levitation magic rune, but one concerning energy expression.
This kind of energy-expression magic rune was divided into three steps: energy intake, energy conversion, and energy output.
The energy intake and energy output steps alone were fixed effects found in almost all "energy sources," so they were not worth mentioning.
What concerned Angel the most, and what he found hardest to understand, was the second step—energy conversion.
The reason this Magic Cottage had endured for a thousand years was that its energy source was not the magic crystals Angel had previously guessed at, but wind.
Wind Island possessed an inexhaustible supply of wind power. By converting wind into energy capable of driving magic runes, it had kept the Magic Cottage standing for a thousand years.
It sounded somewhat reasonable, but actual implementation was exceedingly difficult.
The subject of "energy conversion" had always been a popular research topic in the Wizarding World. When Angel had taught at Ashilia Academy, he had heard of several mechanical alchemy teams tackling this subject, though they had achieved little. They had, however, developed many byproducts, such as Energy Stabilizers.
Even when Angel had met Book Elder, one of Savage Cave's three great ancestral spirits, the other party had been researching energy conversion.
This showed that research into energy conversion was flourishing everywhere in the Wizarding World.
Energy conversion was not impossible, but manipulating it was extremely difficult. Expressing it through "machinery" or "magic runes" was extraordinarily difficult. At the very least, Angel had never heard of a similar precedent before.
That was precisely why Angel had been utterly stunned when he saw an energy-conversion step within this magic rune.
At first, he