-Ancient and terrifying soul-stealing monsters regarded as one of the most powerful demons to originate from hell that served this dimensions ruler (Belial and Mephisto) and are highly intelligent beings with manipulative tendencies and incredible magical abilities capable of warping reality and interdimensional travel.
-Jedah and Blackheart are of important descent that put them in important roles within the inner workings of hell (Blackheart being "the son" of Mephisto & Jedah being from one of the three noble families). They have rather cold personalities but also an insane capacity and enjoyment of violence when in battle, being shown to be thoroughly sadistic.
-None of the aforementioned things were enough however as they had a desire for power, holding plans of conquest, having ruthless ambitions to conquer realms and subjugate the earth under their rule of thumb, as both staged a rebellion against their respective rulers of hell to overthrow them as a result of considering them unfit for the role compared to them.
-This attempt (attempts in Blackheart's case) would be a total failure however as both end up getting sealed/banished for a time before making their eventual come back (Jedah's body getting destroyed after his attempt to absorb all the power in The Gates of Makai, putting him a century long sleep and Blackheart getting cast out of hell by Mephisto, leaving him powerless) with both getting double-crossed in the way and losing their portion of hell at one point (Ghost Rider killed Blackheart, freeing the other Spirits of Vengeance, and gaining rule of Blackheart's portion & Ozom betrayed Jedah and caused his downfall, taking his place as the ruler of the Dohma lands).
-They are lords of their own demonic dimension and in-general both seem to just can't die, getting back from shit that would've certainly killed almost anyone without much issue, including both being completely destroyed then still coming back.
-Marvel VS Capcom with both appaering in MvC despite ironically never being in the same installment.
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