Board Thread:Theories and Speculation/@comment-25549954-20150524070831/@comment-25549954-20150524092225

Who established the fact that Six Paths Sage Mode is upgraded version or next step of Kurama mode as far as I can tell it is heightened state of sage mode so it's a different thing a different type of Senjutsu chakra called Six Paths Senjutsu chakra is involved which he can also combine with Kurama mode. In terms of power Six Paths Sage mode is powerful than Kurama mode, and Kurama mode is next step of nine-tails chakra mode. And to answer your question by mixing two modes he can become more powerful, putting it simply 1+2=3 and 3>2. 1 being KM, 2 being SPSM and 3 being new mode.