Prologue to Phyresis

Poison's oldest problem is landing that first counter without a creature ever connecting; this solves it at instant speed while replacing itself, so priming the toxic gears costs nothing in tempo or card economy. The counter goes on each opponent at once, which is the detail that matters: a lone poison counter is trivial, but seeding it broadly is what turns every subsequent proliferate into multiplication rather than a single wasted increment. Cantrips have always been the connective tissue of blue control, keeping the card count level while the deck stalls; this one performs that same clerical duty while quietly advancing a separate, unrelated route to victory. The dual purpose is the design trick worth noticing: a hard win condition wearing the costume of a smoothing effect. You run it happy for the draw alone, and the ten-counter kill accretes as a byproduct of a full control game rather than a commitment you had to lock into during deckbuilding. That framing keeps it from being filler in a proliferate shell, because it never asks the deck to abandon its natural game plan to accommodate the poison plan; the two occupy the same slot without competing for it.