Master Of Martial Arts Has An Advanced Optical Brain - Chapter 13 - Martial Artist Exchange

Oosuki Masato is an ordinary high school boy who is magically transported to an alternative world, but for some reason his doting, over-protective mother comes along as well.

I wasn’t hit by a truck, nor was I struck by a thunderbolt, yet here I’m inside Hunter X Hunter world, and I even have a system, but it’s really a weird one, it always gives me these kinds of choices:

【1：Join the Ryuudan. Reward: Magma Fruit.】

【3：Destroy the Ryuudan. Reward: Ice Fruit.】

【2：Ignore the Ryuudan. Reward: Fire Fruit.】

Allan sighed, “The problem is I’m really an indecisive guy…”

The world that nurtured the civilization which reached the pinnacle of magic was on the verge of destruction.
The last survivor transmigrated to the past, when the magic civilization started growing, as countless mages were still fumbling their ways through the thorny paths of magic knowledge.
He, who came from the end of the magic era, aim to reach the pinnacle of magic.

Three years ago, to defeat the Demon God who was trying to destroy this world, thirteen Braves were summoned from another world. Each of them had varied ages and gender. Each of them was bestowed with cheat like powers not normal in this world.