From publisher blurb: Ninja, mysterious, silent and deadly. This concise supplement for Kaigaku (plus the Black Hack and other OSR games) has setting information about shadow warriors, plus two new ryu. One is for an unaligned ninja family and the other is for the new lesser clan, the Horokame. Learn how to create illusory doubles or project your mind to find out your enemies' deepest secrets. There's also a brand new adventure, Ninja Attack! You can play this scenario with your group or as a highly replayable solo option.