Zof Consumption is the black MDFC that I'm most uncertain about
Regional Whitebeard (~US$1,000) This alternate art version of a card that was originally part of the Paramount War [OP-02] expansion has a high value stemming from three sources: the fact that its awarded as a prize for those who place in the top 16 of the current regional season, the popularity of the character it depicts, and the cards high level of viability within the metagame

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It That Heralds the End If you get It That Heralds the End out on turn 1 with Ugin's Labyrinth into Urza's Incubator on turn 2, you can cast a 7-drop Eldrazi
Shalai is strong
It changes only the total cost players pay