From what i seeing that Naruto do not know how to use the black orb because he let Madara hit him here
Plus, he could have used the orb to pin Madara down while there were close up
I believe those black orbs are jutsu for ornament or fashion,unless the tail beasts remind him about the orb power .Similarly Kurama have to remind Naruto that he can merge Sage mode with his chakra in the war arc.
Somewhere during this part of the manga ,kurama remind him about the biju sage mode he used against Nagato
You must be registered for see images
Plus, he could have used the orb to pin Madara down while there were close up
You must be registered for see images
I believe those black orbs are jutsu for ornament or fashion,unless the tail beasts remind him about the orb power .Similarly Kurama have to remind Naruto that he can merge Sage mode with his chakra in the war arc.
You must be registered for see images
Somewhere during this part of the manga ,kurama remind him about the biju sage mode he used against Nagato
You must be registered for see images