can't believe you post something like this.
Juubi has 10 tails. Count again.
maybe you don't understand about this.
SO6P had 2 sons.
Elder son - power of the eyes. all about darkness. special eyes. Yin
Younger son - power of the body. Yang
Only those with the MS eyes have eyes can control, like human; genjutsu, etc
Juubi has one single eye. when not in use, it has to be blindfold. Obito & Madara also have link.
Madara need some time to summon something from the moon, and that mean end of the world.
Some 8 & 9 tails' chakra were consumed into Juubi. Obito want to start, but Madara said not yet, as he want to be 100% that need the actual 8 & 9 tails. Perfectionist. But unfortunately (is fortunate for the Allied) Madara may be tired.
When fighting Kages, Madara tests quite a few things (testing) such mentioned. This could cause much of his chakra used. Also he told Obito that he wanted to test (again, testing) so as to confirm more of his theory.
Somehow Kabuto took him out using edo tensai. But Madara wanted Nagato's power Rinnegan, which like what Nagato revived Leaf Village people back to normal life. This could be means although both are for revive but had side-effect.
Anyway both were sitting on the Juubi........................................