CardName: Purge by Blood
Cost: {gw}{b}
Type: Instant
Pow/Tgh: /
Rules Text: As an additional cost to cast Purge by Blood, pay X life.
Destroy target nonland permanent with converted mana cost X.
Flavour Text:
Set/Rarity: Link's Unplaced Cards Rare
Purge by Blood
R
Instant
As an additional cost to cast Purge by Blood, pay X life.
Destroy target nonland permanent with converted mana cost X.
Nice. Would actually be printed costing either
or 
, of course, but yes, I like this idea.
You don't think they'll revisit HC costs, like on the Bant Sureblade cycle?