Thread:Njalm2/@comment-26461986-20130329053157

Most of Daikoku's story for getting the Rinnegan is based on my fanon series:

Mystery behind his Clan Lineage: He was the child of Rin Batsu (daughter of Kiba Uchiha and Meiro Uzumaki. Therefore he had the required Uchiha and Uzumaki DNA in him.

Why did a Uchiha and Uzumaki couple marry ? : Well, we all know the Uchiha's and Senju's are arch rivals. In this case, they married to ensure that Reikaigakure would stay in peace and by getting Rin Batsu an outsider and a native Meiro to get married, there would be peace within the outsiders and natives.

Mystery on how he got the Rinnegan: He worked as a spy within Kirigakure ANBU during a mission. He was caught the act and was subjected to harsh punishment which caused him mental pressure, anmesia and they sealed his Sharingan, Mangekyou Sharingan, Rinnegan, Ice Release (his Batsu Clan trait from his mother). Daikoku however managed to escape their clutches and accidently wnt to a distinct energy field which caused him to travel to the past. During this time-travel, his Rinnegan Seal and the seal on Yin-Yang weakened. (all this will happen in the future timeline of my fanon series and I will make sure I give more complete account has the series moves ahead)

He was later found by Kiba Uchiha who saw the potential within Daikoku and asked him to join Ikigai. Daikoku refused and went into a battle against Kiba trying to learn about himself. During the battle, some amount of his past memories would mentally destabilize him causing him to break his Rinnegan seal and use the paths.

Rinnegan benefits: Unlike Madara and Pain, Daikoku can use only his Rinnegan derived techniques. He will NOT gain the ability to learn all Five Basic natures because of the seal placed on him, except for Yin, Yang and Yin-Yang. Like Pain, he WON'T be able to degrade his Rinnegan to Sharingan/Mangekyou Sharinan. He WON'T be able to access his Batsu trait: Ice Release.

P.S: I will explain a lot of it in detail when my fanon series needs the details, somewhat like how they explained Kakashi's Mangekyou later during the War. Waiting for your approval and will answer any doubts you got. 