@Lady:
I wouldn't say it was for no reason. It's always been his potential, what with him being a jinchuuriki. It's always been pretty obvious that the previous ways in which the Kyuubi's chakra manifested weren't stable. He simply gained control of it, so it's not actually a power-up since he's always had that kind of power inside him. Sage mode however, was a power-up.
Yeah I guess that's true but I was talking about the "sensing evil" thing. It just doesn't seem like something the Nine Tails can use. Isn't he supposed to be an embodiment of evil and hatred? Well….that would kinda explain it then..... FFFFFFFFFF-