Rally the Monastery

Cast anything else first and the printed four-mana cost drops to two: that conditional is the whole point of the card, not a discount stapled on top of it. At full price, a modal instant that makes two prowess Monks, hands out a split +2/+2 pump, or destroys a creature with power 4 or greater is a fair-to-slow effect. Resolve a cheap spell before it and the reduced cost turns it into a payoff for a deck that was already going to spend its turn casting spells, with the Monk tokens folding back into that same engine on the following turn. The modality is what keeps it live across board states: the destroy mode gives a spells deck a rare answer to a large threat, the pump mode turns a board of small bodies into instant-speed lethal, and the token mode rebuilds after a sweeper. Each mode is deliberately modest on its own, because the spell-count clause is carrying the weight. It rewards a texture of play (lead with a one- or two-mana spell, then chain into this) rather than a specific two-card pairing, which is why it belongs to a strategy rather than a combo. The result is a self-discounting instant that asks you to sequence your turn around it, not merely to have four mana untapped.