Uncage the Menagerie
The variable does double duty: X is both how many creatures you find and the exact mana value each one must have. That coupling is the entire design. You cannot grab four random bombs; you assemble a list of differently named creatures that all happen to cost the same number, then pay enough to dig for all of them at once. The clean lines fall out of the math: cast it for two and you fetch a pair of two-drops, cast it for three and you pull three three-cost cards, and so on, with the real work happening in deckbuilding, in how densely you stack a single mana value before the spell ever hits the stack. Green has long had Diabolic Tutor analogues that fetch a single card at sorcery speed; tying the search count to the cost changes the payoff curve so every additional creature you want to reach costs more mana. Reveal-to-hand rather than to the battlefield is the restraint that keeps it card advantage instead of free deployment: the bodies it finds still have to be cast afterward. This is a builder's tutor, and it pays out in proportion to your discipline: pick a number, commit your creature suite to it, and the spell rewards you for the concentration; hedge across the curve and it finds you almost nothing.
