its the same as any other heavenly demonic cult manhwa, mc was betrayed and is fighting to become the cult leader, orthodox sects are corrupt, etc. etc.
Previous artstyle had some charm to it, especially with how the characters were drawn but after the hiatus it seems the artist was changed unfortunately. The plot itself wasn’t anything new but i was reading for the artstyle.
A typical cliché story about the youngest son who is secretly the preferred child because his mother is the powerless one who happened to be his father true love and his father has no qualms of pitting his sons against each other and use meritocracy and achievement to appoint a heir. As usual betrayed MC is back to gain power and become OP