Just a guess. I remember seeing some threads about how Madara wiped out the Uzumaki cause he felt they were a threat to his plan. So maybe he did wipe them out & has something of theres that can stop Obito.
I think RIN is Madara's trump card. He is going to resurrect her and fuck her right in front of Obito, causing him to have an emotional breakdown and thus losing control of the ten tails.
I think RIN is Madara's trump card. He is going to resurrect her and fuck her right in front of Obito, causing him to have an emotional breakdown and thus losing control of the ten tails.