Board Thread:Theories and Speculation/@comment-31186252-20170209020743/@comment-734582-20170210164255

Elveonora wrote: Perhaps they could be brought with Rinne Tensei, but who knows how that works. Presumably, it uses the Rinnegan's power over the soul to call a particular one back, and then forms a new body with Yin-yang release. Of course, it creates the question whether a Rinnegan owner could properly target Ashura and Indra. But Hagoromo could call back random kage he never met before without their DNA.

So i guess that if you killed the current transmigrants and immediately cast Rinne Tensei, you may be able to recreate Indra or Ashura. On the other hand, considering Naruto and Sasuke could talk to Hagoromo but not to their own transmigrants suggests that perhaps, Ashura's and Indra's souls are different now and no longer truly distinct.