I see this from time to time and I thought that I'd add my two cents on the matter. How much power someone gets from being either a complete demon or a partial one seems to be very inconsistent in this series. Even from the first game, after defeating Griffon Dante questions why he's still trying to fight despite being so badly wounded and Griffon states that he must stop Dante because he has seemingly surpassed Sparda and is a threat to Mundus. Yet Dante is only half-demon which would make you think he should only be half as strong as Sparda, if any demon at all. Agnus (who is now a partial demon) even brings up this point when he questions why there's so great a difference in strength between them and Dante goes on some spiel about how being more human is what gives him strength. The way
I view it personally is that by fighting demons and surviving constantly in his quest for revenge, Dante acquired a zenkai boost a la DBZ whereas most powerful demons in the DMC-verse seem complacent and don't seem to do much fighting if at all anymore so that allows Dante to close the gap. But don't get me wrong, I'm not trying to say that any of you are wrong, if only because I don't think there
IS a right answer, perhaps as a result of the series passing through so many hands.
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