Slightly off-topic:
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About DmC2's story:
There's something I had forgotten to bring up; while the twins could both still be Nephilim they could still have changed completely in a "Spiritual" (Soul) sense.
According to their new "Soul Class Standards" they've probably crossed over to the other side.
Dante could be a Demon but with Angelic tendencies, while Vergil could be an Angel with Demonic tendencies (or vice-versa).
[Dante could be classified as a recently crossed over Angel that appears Demonic, while Vergil could be a complete Demon that appears Angelic.]
But I'm sticking with the former for now, since in my mind, that's the theory that makes the most sense. It sets Dante up as an Angel King, given that D0NNI1E said he had planned for Dante to sacrifice himself with the Sparda sword (Force Edge) to save humanity from Vergil.
[Who is an Angel because he views himself as "Immaculate" but in reality, is a Dark Angel who became a Demon King. D0NN1E said that Vergil is now officially more powerful than Dante at the end of Downfall, so having Dante impale himself on the Sparda/Force Edge sword would probably be the only way to defeat Vergil... after a lengthy final boss battle, of course.]
Dante dies, but then is probably assumed to become a Angel King in the process due to the fact that he became a martyr to save everyone else.
As for the actual Nephilim King, Nero could probably fit the bill, that is if Dante and Kat ever got together. It'd be a "perfect fusion" of Angel, Demon, and Human Sorcerer traits, making him the "True Nephilim King."
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Back to fully being on-topic:
As for the fate of the actual game itself, it may be possible to make the sequel for the 3DS with a lower budget, thus firmly ending the series so that we can move on to other, newer franchises with similar supernatural and combativeness traits.