Sway of Illusion

Color-changing has always been a mechanic in search of a reason to exist: recoloring a creature only matters when a color-specific effect is already in play, which is rarely the turn you want to commit mana to it. The design trick here is to bury that fragility under a cantrip. Because the spell replaces itself, it costs no card even when the color swap accomplishes nothing, so it functions as cycling-adjacent filler that occasionally cashes in for a real play: slipping an attacker past a protection-from-color blocker, dodging a color-keyed removal spell, or turning a whole board the right shade to push damage through. The "any number of target creatures" clause is the quietly generous wrinkle, since recoloring an entire attacking force costs exactly the same as recoloring one. That breadth nudges it from a narrow trick toward something closer to a combat reset, though the windows where it bites are slim enough that it has mostly lived as a value cantrip with a contingency stapled on rather than a card anyone assembled a deck around.