Top cards: Emrakul, the World Anew (~$125 borderless foil), Ulamog the Defiler (~$85), Nadu Winged Wisdom (banned in Modern, Commander powerhouse), allied fetch lands
It also at least adds a chance that you take out your opponents threat since you already know your blocker will be destroyed
The value of X is calculated only once, as The Lord Master of Hell's ability resolves
This opens up a horrifying possibility: There are a non-zero amount of games of cEDH in which youll just kill yourself with Necropotence
He wants you to be making Blood Tokens, which are slightly less effective Clues, and then using the Blood to summon your creatures directly from your hand
Cards like Arc Trail and Dromoka's Command which are some of the more common removal spells to get two for ones with at two mana are unlikely to hit high value targets and are both rather dependent on the right situation