Springleaf Parade

Two effects stapled together that pull in opposite directions, and the friction between them is the whole design. The X spell pays for a swarm of changeling tokens whose only combat trait is that they count as every creature type at once, so they feed tribal payoffs, convoke, and sacrifice fodder without caring which lord you drew. Then the static line quietly converts every creature token you control into a mana rock: not just the Shapeshifters it made, but any token elsewhere in your engine, tapping for any color. That second clause is where the card stops being a token generator and becomes a ritual with legs. Cast it for a large X and you have both the board and the mana to spend on it the following turn; cast it small and the tokens are still bodies that fix your colors. The tension is that both halves want to go wide, but the mana ability rewards you for having already gone wide elsewhere, so the ceiling scales with how many token producers surround it rather than with the X you paid here. This is green's old habit of blurring the line between army and resource pool, the enchantment that asks you to spend creatures as mana rather than swing with them, and the changeling clause is the connective tissue that lets a token-matters shell and a tribes-matter shell run the same card.