Naruto Thread (Spoilers For Sure)

He got part of the 8 tails chakra from when Sasuke brought back the one tail he cut off in his fight against Hachibi.
He got part of the 9 tails from the Gold and Silver brothers who KAbuto summoned.

I see, thanks. I didn't realize they kept that chunk of tail when they found out it was a clone. And yep, I remember the Gold/Silver brothers story of raging inside the Kyuubi, haha.