Board Thread:Naruto Discussions/@comment-25294339-20141101162145/@comment-4685024-20141101165808

Only Nagato could truly utilize it in the way you are describing due to having his Rinnegan flowing through 6 different bodies. This allowed only body to fully revive the other because while one Rinnegan user was dead, another body with the same Rinnegan was still alive to heal/revive them.

Nagato's use of the Rinnegan was extremely abnormal, despite it being the first one we saw. A normal user of the Rinnegan would, of course, be unable to revive themselves from the dead, due to them being dead. Also, if they were severely injured or near death, the user may not have enough strength or chakra to summon the King of Hell to heal themselves.

I don't consider it a hack power per say, since it is the Rinnegan, the eyes that the Sage of the Six Path had himself. Of course they are going to be supremely powerful. Just like the 10-Tails jinchūriki had insane amounts of power, it's not "overpowered" because it is suppose to have that much power.

Also, we need to consider that the 6 Paths are not technically alive, but just remote-controlled corpses. The King of Hell may not be able to bring someone back to life that easily, it may have been just him (or it) reconstructing the body and chakra rods so they could move and be controlled again. However, that is just a thought.