Hello!! This drama is from a Chinese series called "the lost tomb" here is the chronological order of it:
Mystic Nine [optional]
The Lost Tomb.
The Lost Tomb 2.
The Lost Tomb 2: Explore with the Note.
Ultimate Note.
Tibetan Sea Flower [Unaired] ...
Tomb of the Sea.
Reunion: Sound of the Providence.

The journey can be so confusing, but I found it fun sticking the pieces together LOL. I watched the ultimate note before knowing about the other seasons, so I'd say if u just want a show to watch u don't have to watch the other series to understand! I watched most of the series and they're REALLY GOOD. Even though the cast changes a lot the iron triangle is lovable in all <33
Here is something I wrote the moment I finished the drama
Overall: I LOVED THE DRAMA OMG! THEIR CHEMISTRY IS AMAZINGGG  ZHANG IS SO HOT JKRGLKERG.  ALSO  IN AN INTERVIEW, HE SAID THAT WUXIA IS LIKE A PUPPY. I NEED A CONTINUATION