Madara said a good amount of that just to hurt Obito, but most of it was not true. Madara did not pick Obito, as he was old, immobilized, and stuck underground. Black Zetsu chose Obito, planted darkness in his heart by manipulating the events leading to Rin's death, and then proceeded to be by Obito's side for the rest of his life, teaching him how to manipulate others or doing it for him. Hell, they say that whenever Tobi acted like a goofball it was really White Zetsu, and whenever he acted seriously it was Obito. But I disagree. Whenever Tobi acted seriously, and began claiming to be Madara Uchiha, it was not Obito but rather Black Zetsu. At a certain point, Obito stopped using White Zetsu to become Tobi and started using Black Zetsu to become Madara. |
Good comparision, actually, I never thought about that.
It would be a good idea to Kishimoto explore a little about Zetsu and Black Zetsu. Not just because they manipulated the entire shinobi world, but because they know intimate secrets about the most important villains: Kaguya and Madara. They know their weaknesses and all their plans.
If I was to make a comparision, I would say they are the "evil" incarnate, because they did not care if a entire family was to be slaughtered, which happened with the Uchiha, nor they did care if a person was scarring themselves as Madara did when he left his clan, or Kaguya who is still seeking for revenge.