Shadow on the Moon

Anyone who could construct a stable Spell Model could become a Wizard — that was the Wizards' ultimate secret! Having been given a new life as the son of an aristocrat and armed with a super quantum computer from his past life, Spell Models game as easily as breathing to Merlin. With this overwhelmingly huge advantage, would Merlin become the greatest Grand Wizard of all time?

EndlessFantasy Translation 

A Wizard's Secret

J_Squared

The night was as dark as a deep lake. Although Merlin and Aruba had decided to go to Sky-piercing City, they had to wait until tomorrow to start their journey.

Ogman now stood before Merlin and Aruba. He had an intuition that both of them had great powers, far surpassing any contenders he had seen, so he had purposely come to them for guidance.

It just so happened that Merlin and Aruba could take this opportunity as a pretext to thoroughly understand this world's power system. Having this comprehensive understanding would allow them to aid the people here in breaking free from this Latitude Cosmos.

"How do you usually improve your strength?"

Sky-piercing City!