To be honest with you guys, I feel like Kurama is the strongest of all the tailed beasts, but there are discrepancies in their power.
Kurama= Seven tailed beasts. He basically strangled them and matched their TBB and it may have not even been a full powered one.
You take the seven tailed beasts and add a small tentacle from the hachibi, then add two shinobi who have Kurama's chakra into Gedo Mazo, and you get a being that OVERWHELMS Kurama and the Hachibi.
I mean, considering that Kurama took down seven tailed beasts without too much difficulty, you would think they could put up more of a fight. Especially with the 2nd strongest Bijuu, a Sharingan user and a Taijutsu master there?
Tobi and Obito don't count for the Jyubi's side since they are basically only fighting using it at this point.
So Kurama at full power along with Hachibi *may* be a match? I still doubt it.
There does not seem to be a definite rule concerning the strength of the tailed beasts, but it seems certain that Kurama is still greater than the other tailed beasts and Shukaku is the weakest (being taken out by a Genin Naruto).
We can definitely conclude (and Kurama confirms this) that Gyuki is the 2nd strongest of the tailed beasts as it took a fairly skilled Shinobi (Sasuke) to even THINK about going up toe-to-toe with him and he still failed to win.
We can't really count the fight with Kisame because Bee was unable to use full-hachibi mode.
I mean since Naruto and Kurama came to terms, Bee and Gyuki have basically taken a back-seat.
