Re: "Perfect" Kyurem

Just one detail though... the tao trio doesn't have a "trio master" (unless Kyurem is an internal trio master). Alright... nothing's saying that it needs one, but all other trios have one. And introducing it in a later generation is not that unusual... we had Lugia introduced a generation later, then we have Regigas introduced a generation later. I don't really think importance to the story makes much difference. Arceus himself was important to the Generation IV story (well, the mythology / backstory) but he wasn't even obtainable except through some event.

Rayquaza serves as "trio master" in Hoenn. Mesprit, Uxie and Azelf have no master, unless you were to count Arceus, but it is already tied to the Sinnoh dragons. Lugia isn't directly related to the Kanto birds either, only in the 2nd movie. In Gold, Silver, Crystal and HG/SS, Lugia has nothing to do with the birds. And again, the Regis were not a part of the direct main storyline, so having Regigigas added later wasn't a big deal. But again with Arceus, it was still part of Gen 4, and even if it was only available through events, it is still available.

Since the Unova dragons all revolve around Taoism, it would be rather pointless to just add the Original Dragon to Gen 6, which will be based on something else. It would be GF basically saying "Just put it in there somewhere".

Two ways of handling that:
- Code it into B2 / W2 (or B3 / W3 if such sequels were to exist... but I feel that's getting a bit carried away) and then just make it not tradable back to Black / White. In other words, it would be sort of a "Generation 5 and a half" Pokémon.
Such a thing has never been done before, but similar stuff has been done with items (the GS Ball, for example).
- Make it an alternate forme of Kyurem... a "perfect" forme. Think DBZ... Cell's perfect form could only be achieved by absorbing Android 17 and 18. In a way, he was no longer Cell at all, but a combination of those 3 beings (yet he was still called "Cell"). It could be the same way with Kyurem... even though the original dragon isn't truly Kyurem but a combination of Reshiram, Zekrom, and Kyurem... maybe he could still be called "Kyurem" if Kyurem is the one absorbing the others. (Except there's no evidence that any absorbtion is even going to occur)

Then the OD would be useless in B/W. Since Freeze Shock and Ice Burn were coded into B/W, compatibility has already been accounted for, so adding another Pokemon and making it non-compatible with the previous games (especially with it being a Legendary Dragon that everyone would want to use) wouldn't make much sense.

Making another forme for Kyurem wouldn't work well either, that would make the other 3 formes seem rather pointless. Having a perfect forme implies that it would be superior to the other formes. Why use Kyurem's normal forme, Black Kyurem, or White Kyurem when you can just have the Ultimate Forme? Still Kyurem is not suggested to be the Original Dragon in the games, that's only fan speculation. That is how Kyurem is different than Cell. And considering that Wuji and Taiji are direct opposites, with Kyurem and its formes representing Wuji or a combination of either Yin or Yang, a being associated with Taiji would have to be a totally different creature in being absent of Wuji.