Manga Like Undead King: Teihen Bouken-sha, Mamono no Chikara de Shinka Musou

God gives each person one special skill in life, to help them fight monsters. Chrome, who longs to be an adventurer but never manifested any special fighting skill, refuses to give up on his dream. So he works as a low-ranked adventurer doing miscellaneous work while being scorned as useless by others. One day, he is left behind as bait in order to let the others escape from the monsters, and loses his life in the process. That is when Chrome's special skill is activated. The skill is "Revive." With this skill, which allows him to come back to life only once, he miraculously survives - as a skeletal monster named "Wight." Chrome despairs at his monstrous appearance, but then he remembers the story of how monsters evolve and change their forms as they become stronger. Believing that he could regain his human form through repeated evolution, he continues to hunt monsters. And in the process, he acquires multiple skills that are only available to non-humans. The power of monsters, combined with human intelligence. Turning adversity into opportunity, Chrome sets out to become the strongest adventurer ever. (Source: Hyke Comic, translated)