Dysfunctional - An Assassin's Guide to Reincarnating in Another World - Chapter 2 - 1 - Three, Two, One

High school student Mikoshiba Ryouma was summoned to a different world in the middle of a war. Sensing the malice from the one who summoned him (a summoner of the O’ltormea empire), he uses his martial arts to run away, killing important people of the empire during his escape. After the escape, he rescues two twin sisters from the hands of thieves. The sisters who can use magic, swear to serve him as subordinates. Thus, Ryouma begins his journey on the path of the supreme ruler.

Ian was an ordinary guy on his way to work when he suddenly found himself in a strange and dangerous world ruled by dark races like vampires, werewolves, and demons. Transmigrated into the body of a lesser vampire, Ian must quickly adapt to his new reality where survival is a constant struggle.Just when all hope seems lost, Ian discovers he has a unique advantage: The Strongest Body Customization System, which allows him to modify and customize his body by consuming biomass. With this golden finger, Ian starts to turn the tables, designing bone claws and other enhancements to give him an edge against the terrifying werewolves and other supernatural threats.But as Ian learns more about the Curtained Imperium and the rigid hierarchies of the vampire race, he realizes that defeating his enemies is only the first step. To survive and thrive in this dark and brutal world, Ian must rise through the ranks, uncover the power of his system.Need to fly? Customize a pair of angel wings!The body is small? Add hundreds meters of height and become bigger than Godzilla!Need a weapon? Customize bone claws and kagune on the spot!

This is the story of a modern sailor who was accidentally reborn as a soldier of the Brazilian Expeditionary Force, and finally became the largest plutocratic family in Brazil by virtue of his foresight.

- Description from novelbuddy

Always looked down upon by others, Ji Feng gains technology far more advanced than the present, as he discovers its abilities, he begins to walk a path far from ordinary. With X-ray vision allowing his to find jade stones in rocks. With this futuristic technology, Ji Feng accomplishes something no-one can compare to. This is the beginning of a legend.

- Description from Novelupdates