Everyone has just found out about hagoromos brother. This was a shocker to me. How could kishi just introduce him and give us no explanation on him. I've been thinking though and i haven't see any predictions like this one.
Im sure everyone remembers the legendary hashirama and madara fight. Well in one of the panels hashirama is shown sensing someone over the cliff but he brushed it off and ignored the feeling. Hashirama even said he saw his friend(madara) die that day.
Well madara obviously must have been revived by someone just like obito was. I believe that the brother found a way to be immortal. I think the brother corrupted Indra and he is the reason Indra had a problem with ashura gaining all the bijuus power.
And since Indra is confirmed dead since he is "haunting" sasuke, then that means that hagoromos brother must've revived madara. And he also told madara this whole plan. I believe that the brother is the spiral zetsu.
I think madara is comin to an end and it sure does seem like it because Naruto is gaining a new power and so is sasuke. But i think before madara dies the brother will step in and save him. There is also another possibility of his brother being jashin. That way he could also be immortal. But yes i don't believe that madara is the final boss and i think they will have to face his brother very soon. Please give me feedback of what you think