A Mastermind? No, I'm just the Live-In Son-in-Law - Chapter 21: The Emperor

A world filled with heroes with superpowers. A world attacked by calamity fiends. A modern world filled with wonders and dangers.

On an ordinary day, Lucius stumbled upon a strange, run-down shop. At first, he assumed it was abandoned—until he stepped inside.[You have entered the Universal Alchemy Store.][Congratulations! You are now the store’s owner.][Please craft your first potion.]Lucius blinked. 'What kind of joke is this?' But as if guided by an unseen force, he followed the instructions. Minutes later, his first creation was complete.[Love Potion: The drinker will fall in love with the first person they lay eyes on.]Lucius swallowed hard. 'Wait… does this actually work?'Before he could process it, the shop’s door swung open.Standing in the entrance was no ordinary customer—she was an elf. Long, pointed ears, mesmerizing green eyes, and a body sculpted by the gods. A visitor from another world.A dangerous thought crept into his mind.'Should I test it on her?'

Etius, a game that no one has cleared.

The moment all possible strategies failed, “Student Frondier ?”

I became an Extra in the game, I became Frondier!

“Change the fate with this?!” Duplicate everything to carve out my destiny!

“Jiang Yu transmigrates into a novel and becomes a side character in the book.