I found something, I was reading absolute sword sense Chapter 20
Hae Ak-Cheon was asking the corpse (jongdae-the owner of the sword technique mc learned) how he died and the man they portrayed "a man with golden eye"
A man with golden eye the only one I know that has a golden eye is yu mumu from "invincible mumu"
Actually yu mumu fought jongdae and jongdae survived but on verge of death
And the one who killed him was "Han Jisang"
Woah, thank you for this!
Holy lore
Invincible Mumu Set 200-300 years before Absolute Sword Sense, It follows Yu Mumu during the very early days of the martial world (I can't find the novel to read it, 177 chapters, read on novelupdates)
Absolute Sword Sense Set 200+ years before Myst Might Mayhem,It follows Jin Woonhwi during a chaotic era when the Blood Cult was already established.(already has a manhwa go check it out)
Myst Might Mayhem Set 800 years before Nano Machine,This series features Mok Gyeong-un, who becomes the First Heavenly Demon and officially founds the Heavenly Demon Cult.
(already has a manhwa go check it out)
Nano Machine Set 1000 years before Descent of the Demon God,It follows Cheon Yeowun, a descendant of the Heavenly Demon lineage.(This is the manwha)
Descent of the Demon God Set in the year 2069,It serves as a direct sequel featuring Cheon Yeowun in a modern futuristic setting
(244 chapters,read on novelight)
You can read them non chronological way, except
Decent of the demon god read nano machine first
Since it follows the same protagonist.
Unfortunately no manhwa adaptation yet on
Invincible mumu & Decent of the demon god.
Hope you guys have fun reading (づ￣ ³￣)づ