[quote=@Windicator]Well, this isn't official but I think that one condition for the ExE Evolution is being defeated or maybe even death of a Digimon and it's probably related to the new Omnimon / Omegamon thing call'd Black knight executor 
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That's nothing new, conceptually. See: Death Evolution, See: DeXDorugamon, DeXDorugreymon, DeXDorugoramon.
Looks like a redesign of Omegamon Zwart, to be honest. Looks cool, but the ExE probably has to do with Death X and Death Evolution, which isn't really that new, seeing as SkullGreymon is technically a Death Evolution.