Board Thread:Questions and answers/@comment-25177439-20170106025149/@comment-30155239-20170108023917

Overall, I'd say that Susano'o was the most destructive and overall threatening of the BlazBlue villains, followed by Izanami and then Relius at a distant third.

The biggest factors Susano'o held in his favour over Izanami is in terms of overall combat ability and scope of his evil plan.

While Izanami boasted (not without justification though) that she was unkillable, that was moreso due to the fact that it's more like fighting the Master Unit's angry puppet rather than her being unstoppable in battle. Susano'o almost effortlessly crushed everything in his path once he got his real body back, and he only lost because Ragna had literally the only power that could defeat him (ripping out his soul/Terumi) from his body (the Susano'o unit). For all intents and purposes, he was unstoppable unless he was removed from the Susano'o unit, the same way Izanami can be defeated but she'll never "die" as long as her originator is around to bring her back. Her main advantage was being an Observer, which Susano'o also matchched by absorbing Noel into himself (which raises the possibility he could've done the same to Izanami instead if she had won the Observation battle with Noel).

Susano'o was aware of the Gate leading to the Azure and how to obtain it, how to cancel out even Amaterasu's Phenomona Intervention (by absorbing Noel), and even how to escape Izanami's Doomsday plan. Once Izanami had her Doomsday set to go, she basically just focused on buying time, and her boasts of finding the true Azure ring somewhat hollow when she made no efforts to reach the Gate herself or to get Ragna to the Gate. She was only interested in spreading death.

Even if she did complete her "world of death" master plan, in the long run it's considerably more merciful than Susano'o's master plan of destroying the world then reviving it over and over to get as much hate/fear out of them as possible. By "free", he simply meant that he didn't want to be beholden to Amaterasu's wishes through Phenomona Intervention anymore, and basically wanted to vent out his spite on Amaterasu by destroying every world she reconstructed.

Izanami actually does have a reason for destroying the world, which amounts to the equally petty and "doesn't seem as bad" reason of destroying the world because her original self was tortured and broken by humanity. In summary, the two most evil characters in the BB verse tried to destroy the world because they wanted revenge on everything for their misfortunes.

In conclusion, both were pretty despicable and very competent villains, but my view is Susano'o had the more solid plan and was the more dangerous enemy due to his initiative and sheer power.