FAN 67 Concealed Kong (2 points)
Created when four identical tiles, all self-drawn, are declared as a "hidden" Kong. Thus requiring also a replacement tile when available. You must reveal the Concealed Kong to the others after the hand is ended.
A Concealed Kong is a strong and intimidating "weapon"... which of the tiles is no longer available to the other players!?

DOES NOT COMBINE WITH:
n/a
source: Mahjong Greenbook MCR Rules 2014 (pdf)