煞風掌 is actually not part of Five Ancestors system . It is past down from 五枚 师太and the grand master is actually a Taoist. The actual full name of this system is 煞字自然门五行掌.
master yap is ask to perform every year , sometime you get board by asking to do it every years . So , he mix up some of the Cream of cream technique of Five Ancestors Fist plus 玄女and 煞字自然门五行掌 technique perform on stage.