Tianxia: Spirits, Beasts & Spells is a very good supplement to main rulebook. The biggest advantage of Tianxia: Spirits, Beasts & Spells is the presentation style of magic and description of the supernatural world. Magic, supernatural creatures and mythic places only complement existing information - are not intended to replace them. That's important to me - I can't imagine a setting about martial artist where mages and exorcists are more powerful.
Anyone interested in reading polish language review (or digging to it via Google translate) can read full text here: http://3k10.pl/2016/09/23/tianxia-spirits-beasts-spells/-
[5 of 5 Stars!]