Phantasmaturgy

“What I mean, Mumei,” Vitha said, leaning forward with her elbows on the table, “is this: if you got the chance to be summoned as a hero companion of our new-generation ‘Meir,’ what Oath would you want to be affiliated with? And what abilities would you want to have?”

I tapped the screen, highlighting the abilities section. “Of the seven Oath blessings, I gave this character… well, I’d wanthimto have the blessing of theOath of Malady.”

Tadano Mumei, an assistant game developer of the game: Heaven's Ashfall, was once asked, what if he was summoned to the game world they are developing, and his answer was that.

“Phantasmaturgy:Mind-Illusion magic,” I said. "I think I'll go with this ability if I ever got isekai'd to this world."

I thought that my greatest "What-if" in my life will be just lingering thought at the back of my head until...

... I was summoned as a hero companion, a person that assists the great hero, in that world.

“Hero companion of my daughter… what is your name?”

I swallowed hard, then lowered my head. “Tadano Mumei.”

The king lifted his hand with finality. His next words rang through the vast summoning chamber like an oath sealed in blood.

“Tadano Mumei, assist my daughter with the duty left to us by the Goddess and by the First King of Obelia Kingdom. Let the demons be eradicated off this world!”

⚠️ What to Expect from this Series:

🌀Isekaiwith game elements — LITRPG and clear visible progression of the main character team

🧠Smart, strategic MC— put a lot of thought or strategize everything based on the theory he has studied

🐢Slow-burn progression— focused on depth, worldbuilding, character development and steady growth

🏰Territory-building— frontier management, border defense, and societal reform.

🔥Human vs Demon War— eradication, fate, brutal, and full of gray morality.

🎭Unique magic system—Seven different Oath systems and a lot of different class jobs.