"Might be a conjurable parameter." Body of the fifth lightball?

This fails.

"I do not seem to be able to use 'that lightball' to get a model of someone."

He tilts his head. "Can you try for the other lightballs? In case there is something exceptional about that one."

"Sure -" Conjuring by 'the lightball that turned out to be Tobirama'?

Gets a miniature Tobirama.

"Fascinating."

"I wonder what's up with lightball the fifth..."

"I do as well. Namikaze might have an answer."

"We can ask them!"

Sasuke seems to be almost done with the first - 

(He overheard the discussion, and decided to prepare the Fourth Hokage's summoning first.)

And a new person forms.

He glances around, frowning, and asks, "What is the meaning of this?"

"Hello! We resurrected you! No people were sacrificed."

"How did you break the Death God's seal?"

He concentrates for a moment, then relaxes ever so slightly.

"The Uzumaki clan had a method, apparently," Sasuke says.

"That sort of knowledge was certainly lost. How did you acquire it?"

"I can recreate notes, among other things."

"They seem legitimate to me; the Uchiha boy hasn't lied once. They had asked for my aid in dealing with someone named Orochimaru."

"Orochimaru was a loyal shinobi of the Leaf, last I'd checked."

"He defected after your death. He got caught experimenting on Leaf citizens, unauthorized."

"I'll need to confirm that, before I offer any aid," he points out.

"Does my word suffice, that the one time I met him, he was summoning my brother and I to attack the Leaf?"

" - Is the Leaf alright?"

"Yes. The Third sealed them both. There's a Fifth Hokage now, Senju Tsunade. She's uncontroversial."

He hesitates, then shakes his head. "I still want external confirmation."

"That's very responsible of you. Are there materials of a kind or volume you'd be sure I hadn't fabricated which would suffice?"