That's what I don't get Madara was a sensor in base way before becoming Juubi jin so becoming one his sensory power should be on a while another level but somehow it isn't unless he wasn't in sensing mode.
Wasn't it said that Naruto was the only one to befriend the tailed beast? Besides Kurama in a flashback showed he hated both Hashirama and Madara for what they did to him.
How can Nagato have shinra tensei as a special ability with Madara's Rinnegan? If that was the case then Kakashi or Obito wouldn't both have Kamui and shinra tensei is a six paths jutsu it's not original like Sasuke's S/T or Madara's Limbo.