Reap

The scaling clause is the entire design: this is a recursion spell whose power dial sits on your opponent's side of the board. Against a deck with no black permanents, it sits dead in your hand; against a mono-black deck overcommitting creatures and enchantments, it dumps your graveyard back into your hand for two mana at instant speed. (The clause counts black permanents, not black mana sources, so an opponent's Swamps stay colorless and add nothing to X unless something has turned them black.) Tempest built much of its color pie on this conditional-payoff structure, pricing cards as either blank or backbreaking depending on what sat across the table, and few of those hosers committed to a single matchup as fully as this one. The instant-speed window does heavier lifting than the rate implies: you can hold the card until the opponent has overextended, count their black permanents at the moment of maximum commitment, and reload at the most punishing point in the turn. It rewards a metagame where black stands as a dominant pillar and players will spend deck slots to attack it specifically, which is exactly the environment Wizards was designing hosers for in the late nineties. Strip the targeted-color clause away and what remains is a strictly conditional graveyard-to-hand effect; the whole design intent lives in that one restriction.