I created this thread to show why I think new form of Kyurem is needed and how it would be possibly created, basing on Taosism.
Reshiram and Zekrom are based on Yin and Yang.
Yin and Yang are two opposite forces which are often unbalanced. When one is increasing the other one is decreasing. It can be seen in final battle with N in both versions of game. In Black when Reshiram is winning, Zekrom is losing. In White when Zekrom is winning, Reshiram is losing. They are unbalanced in both versions just like Yin and Yang.
Current form of Kyurem is based on Wuji – the state state of harmony and balance. It is limitless and infinite. That's why I think N's and Ghetsis' last name is Harmonia, because it relates to harmony of Wuji and Kyurem.
The only state of energy that is missing in Tao trio now is Taiji – the state when energy is separated between Yin and Yang, but they remain together combined as one. And I think new form of Kyurem will be based on Taiji – it will be combined with Reshiram's and Zekrom's energies as one. Taiji is described as "Supreme Ultimate" state of undifferentiated absolute and infinite potentiality. I'm expecting new form of Kyurem will be as supreme ultimate as Taiji.
I think in Grey there will be cutscene at Dragonspiral Tower in which Light Stone (Yin) and Dark Stone (Yang) will be combined into God Stone (Taichi), creating new form of Kyurem and N will catch it.