This is a much-needed answer to Sheoldred that will hopefully work to keep her in check, even if just a little bit
The original card had "you draw two cards and lose two life", "destroy target creature," and "cast a spell without paying its mana cost." The last ability was both too powerful and not really black (black could cast a spell out of a graveyard)
Thus when I factor this into the context of my cube, this will see a lot of play
Before we move on, though, I want to bring your attention to Sudden Substitution
Whether in black-green-white decks, which pack Pernicious Deed, black-blue-white "Fiends" decks of the recent Extended season, or black-white Desolation Angel decks in Standard, the Lynx stood as a formidable creature to deal with