Pugnacious Hammerskull

A 6/6 for three mana is a rate green almost never gets to print clean, so this one carries a leash: attack while you don't control another Dinosaur, and it stuns itself, sitting tapped for an extra untap step each time it attacks. The design turns the body into a tribal payoff rather than a beater. Every additional Dinosaur you deploy is a key that unlocks free, penalty-free attacks, so the card is priced as if you will build toward a board where you always control another Dinosaur. On an empty battlefield it is a liability that trades tempo for its own size; surrounded by its kind, it becomes the largest thing green can field this early. The self-inflicted stun counter is a neat inversion of the mechanic's usual role: stun normally punishes an opponent's creature, but here it is the tax the card levies on its own controller for breaking tribal discipline. That framing does the balancing work a keyword ability or an activation cost would do elsewhere, but it lives entirely inside the attack trigger, which means the drawback is conditional and self-correcting: the moment your board fills out, the downside evaporates and you are left holding a wildly overstatted three-drop.