The Lone Necromancer is a Manga/Manhwa/Manhua in english language, Action series, english chapters have been translated and you can read them here. You are reading chapters on www.mgeko.cc fastest updating comic site. The Summary is

The world is ending. Monsters from legends appear everywhere. They eat people, conquer the streets, and begin to make dungeons in the buildings and subways. If you could choose one job in this decrepit world, what would you choose? For a “necromancer” extinction is my playground and death my wealth.