Dragonlord's Prerogative

The price of uncounterable card advantage, set by whether you've committed to Dragons. Drawing four for six mana at instant speed is a fair-but-unspectacular rate on its own: Concentrate did three for four, and bulk blue draw has long undercut this. What the spell is really selling is the conditional protection clause, and the additional-cost structure is the clever part. You don't have to reveal a Dragon; you don't even have to own one. But if you reveal a Dragon from hand or already control one, the spell becomes uncounterable, which turns a refill into a guaranteed refill against a deck built to stop it. That conditional is a tribal payoff dressed as a control card: in a Dragon shell the protection is free, while a generic blue deck pays full mana for a beatable Concentrate-plus-one. The design lesson is in how the cost is gated rather than the effect. Most "can't be countered" riders sit on the card unconditionally and inflate the mana value to pay for them; here the rider is earned at cast time by a deck that was going to run Dragons anyway, so the rate stays honest for everyone else. It is a refill spell that knows exactly who it was built for, and asks that player for nothing extra to get the part that matters.