Madara gives nagato his rinnegan. (obito claims he did but madara is shown to have had the rinnegan, and edo tensei people seem to get back their eyes)
Obito takes nagato's rinnegan.
Madara originally got those eyes from Izuna.
Thereforeeee....Obito is PARTIALLY Izuna lol. just the eye though. No consciousness of him.
and no i'm not saying izuna can see through that eye or something lol, he is dead.