That's actually kinda hard to decide, I guess it would depend on ur playstyle or what build u would like, since u have dark amat, then you could either get thanatos or satan and aim for an offensive burst build (with Shingen as your main soul)
and since dark amat paired with either AW Satan or Amon U would already help u reach 40/45 atk/def debuff, then I don't think you would need ambush anymore. What ex skill you use is gonna be up to you I suppose
I.. honestly don't know if Pluto is a must have for dark teams. if your team is already filled with.. let's say Satan/Amon/Thanatos, Dark amat, Osiris and Hades, then it's kinda hard to think who you would replace just to squeeze pluto in
But for people without dark amat, it would be easy to fit Pluto or Samael in on their dark teams
VoF = Vissicitudes of Fortune
Mordred's 2nd skill that helps you land debuffs easier
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