9 Yang from what I know is mostly internal kung fu. 9 Yin on the other hand has a combination of both outer and inner. I don't really remember 9 Yang having much internal. So there shouldn't be any, should there? Besides I think the new origin of 9 Yang is absolutely HORRIBLE! I prefer the old one of Da Muo. I'm curious, which one do you think is better, 9 Yin or 9 Yang? I personally think 9 Yang for inner (never said, but by the way they describe it), and 9 Yin for outer (because 9 Yang doesn't have much outer, if there is any). Overall......, not too sure, but I'll go with 9 Yang.