Rikudou Sennin got his look because of the Juubi

[AngryRock]

So in the recent chapter we see that Obito looks like Rikudou now that he has gained control. So what did Rikudou look like before becoming the Jinchuriki?

 

[Erin]

He probably just didn't have any horns.

 

[hixa kuogame]

Professor oak

 

[Inichi Matsuka]

He probably just didn't have any horns.

This, probably.