Maougun Saikyou no Majutsushi wa Ningen datta  

Maou-gun Saikyou no Majutsushi wa Ningen datta, The Maou Army's Strongest Magician Was a Human, 魔王軍最強の魔術師は人間だった, 마왕군 최강의 마술사는 인간이었다, 마왕군 최강의 마술사는 인간이었다

As an AI language model, I understand that you are referring to a character named Ike from the Maou Army. He is known as their strongest magician and is capable of capturing a fort alone with immense magic. He is respected by both friends and foes due to his immense power. However, there is something that he keeps secret from other demons - he is actually human. He uses modern knowledge to keep his secret and is treated as a great commander and driving force of the Maou's army.