Relentless Rats

Most creatures pay for their bodies once, in mana. This one pays in deck slots. The rule that a deck can run any number of copies is the entire design: it turns the standard four-of cap into a dial you set yourself, and every copy you draw enlarges every other one already in play. Eight rats on the table make each one a 9/9; a deck stuffed with thirty keeps the late-game draws growing the swarm rather than flooding into dead lands. This is the card that first asked the question (later picked up by Shadowborn Apostle, Rat Colony, and the rest of the "any number" experiments): what happens when the four-card limit simply does not apply? The answer is a creature whose power is a function of redundancy rather than rate, a body that gets better the more you commit to the bit. The tension it resolves is consistency versus ceiling. A normal threat asks you to draw the right mix of pieces; a pile of these asks only that you keep drawing, since every copy is both a payoff and a payoff-enabler. The cost is a curve and manabase dragged toward double-black three-drops you have to flood into, plus the knowledge that a single sweeper unwinds the whole stack at once. It is the rare creature where the deckbuilding decision and the card are the same object.