Skeleton Warrior is a Manga/Manhwa/Manhua in (English/Raw) language, Action series, english chapters have been translated and you can read them here.
[From the author that brought you “Limit Breaker.”] Kim Sojun, a former high school teacher who lost everything playing the stock market and came face-to-face with cruel reality, stumbles upon a heap of gold coins during a school trip. However, the moment he touches a coin, he is cursed and transported to a murim world. He wants to live a lazy and cushy life with the gold he found, but the System won’t let him do it. Not to mention, there are other transmigrators from the modern era who came to this world earlier than him. Surrounded by martial artists and skeletons, the murim life of Kim Sojun begins!