Thunderherd Migration

Rampant Growth has been the template for two-mana basic-fetch ramp for decades, and the design idea here is letting a tribal commitment waive the extra toll. Reveal a Dinosaur and the spell runs at the classic two-mana rate; lack one and you pay the additional mana to bring it up to three, a full mana behind the ancestor it descends from. That conditional tax is the whole point: this isn't a strictly better ramp spell, it's one that only matches the baseline once you've already built around a creature type, and quietly penalizes the decks that haven't. Revealing rather than discarding is the mercy that makes the discount worth chasing: the Dinosaur stays in your hand, so the cost is information, not a card, and the same fatty can pay the toll on every future casting for as long as it sits there. It belongs to the long line of green ramp that ties efficiency to a deckbuilding promise, the way various landfall and creature-type payoffs ask you to shape your list before they reward you. As fixing, it does exactly what its lineage does, dropping a basic onto the battlefield tapped; what distinguishes it is that the tribal reveal isn't a bonus stapled on top but the gate that decides whether you're paying the classic rate or the penalty above it.