One benefit from being late to a series is that I start from the prequel world building and the origin story of the Clans, and Jade.

This short prequel focuses on Pulo, and how he learnt his craft from renowned Jade setter Isin.
We are introduced to the world of Jade which has mysterious power enhancing properties which give the Green Bones warriors the abilities to run the island of Janloons most powerful clans. Pulo does not have the ability to become a Warrior, but he can set and reset powerful Jade pieces which are won by duelling Green Bone warriors.

I really enjoyed the strong sense of justice, morality emitted from Pulo, who does not belong to the powerful clans; rather he is part of a neutral clan and seen as weaker (although his Master Isin is a greatly respected Jade setter across Janloon, and noone would mess with him).

If this is the appetiser before the series, I would say this has really made me buy the rest of the series.