Wild Wurm

A 5/4 for four mana was an aggressive body for its era, and the coin flip is the tax Tempest charged for it: half the time the wurm slumps back to your hand the moment it lands, turning a tempo play into a wasted turn. This is the design philosophy that ran through Tempest's red commons and uncommons, where above-rate stats came bundled with variance rather than a deckbuilding cost. The flip happens on the enter trigger, not on attack, so there is no way to play around it; you commit the mana, you reveal the body, and the coin decides whether you actually got it. What separates this from later coin-flip cards is how clean the penalty is. The wurm does not die, it does not sacrifice, it does not deal you damage on a loss; it simply returns, which means a failed flip costs you only tempo and not material. You can recast it, flip again, and keep paying the four mana until the coin cooperates. That recoverability is what the design is built around: a swingy creature that punishes you with time rather than cards, sized so that the average outcome over two casts roughly approximates a fair four-drop. It is the kind of luck-themed red effect Magic returns to whenever it wants to sell raw power at the price of consistency.