One Piece: God of Space - Chapter 239 Control

Su Yu was in a third rate university when the “Sky Holes” appeared, his school fell through the “Sky Hole” and appeared in the middle of a forest that was teeming with terrifying creatures.

Witness a fearsome transformation that originates from his hand…

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Achieving the power to create virtual worlds.

To expand his world, he needs to devour other worlds.

As such, the world ushered in the most greedy, sly and terrifying existence in the world ——— The Gamer

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Silas Blackwood wakes up with a machine in his chest – his missing mother's parting gift to help him survive the war with the Fae. This “system” grants him bizarre abilities: neuromancy (magic of the mind), biomancy (magic of the body), and essomancy (magic of souls and essences). Oh, and it fused a leviathan's mana core into his body. Because why not become part sea monster?At Arcanium University, a military boot camp churning out mage knights, Silas finds himself targeted by rich brats who think being born with a silver wand up their ass makes them special. When they leave him for dead, Silas decides it's time to show these spoiled kids what real power looks like.As Silas grows stronger, he discovers he can upgrade himself by absorbing essences from magical beasts and demons. Just when he thinks he's got a handle on things, Silas learns his mother's alive, and now he's got a new mission: a rescue that'll take him and his friends straight into the depths of Hell.

Our protagonist Caam is a man from Earth that was reincarnated into this world as a demon. In order to survive, he spared no effort in avoiding the sparks of battle and without noticing it, he became strong himself.