Petrified Wood-Kin

Bloodthirst was built around the gap between a creature's printed body and what it could become if you bloodied the opponent first, and most of the cycle aimed low: cheap creatures that picked up a counter or two off chip damage. This one inverts the proposition. The base 3/3 is a stub for seven mana, but the bloodthirst here is unbounded, a replacement effect that loads on one counter for every point of damage your opponents took before it resolved. Push through with an early board and it arrives far larger than its cost suggests. The two protective clauses are what make that payoff worth chasing: uncounterable means slamming it doesn't hand a control opponent a clean window, and protection from instants closes the most common answer for a creature this size. A removal-heavy opponent can't bounce or burn it at the moment it matters; they're pushed toward sorcery-speed answers or board wipes, exactly the cards a ramp deck is built to play around. So the whole package resolves around protecting a single number: the body's value is fixed the instant it enters, and the two abilities exist to keep that count from being undone for a single card. The cost is steep and the floor is unappealing, the honest price of a green threat that pays you for dealing damage first and hands back a body that is genuinely hard to remove once it sticks.