Board Thread:Theories and Speculation/@comment-26889573-20151008053113/@comment-6769189-20151016231236

It doesn't have to have Yin Release. It grants chakra. Madara and Obito called its tree form Shinju, like a billion times AND we don't have a depiction of the original Shinju. Whether it did or didn't have the Rinnesharingan, it is the source of all thise abilities. It bestows those abilities. It is the source of all chakra, all KKG, and all styles.