Giant Cindermaw

Red has a long habit of taxing the act of gaining life rather than merely dealing damage, and this pairs that instinct with a body built to end games. A 4/3 trampler for sits ahead of the curve for a color that lives on tempo, so stapling a lifegain lock to it costs the pilot almost nothing. "Players can't gain life" reads as symmetric, but red decks racing an opponent to zero rarely need to gain life themselves; the restriction lands squarely on the strategies that depend on climbing back out of range. Trample compounds the pressure: blockers thrown in front still bleed excess damage through, and the lifegain those blockers were meant to buy time for is already switched off. The clause is aimed with precision at everything most likely to survive a fast start, whether that is a stabilization spell, a ramp deck buying turns, or a control plan built around fogging and healing back up. Sulfuric Vortex and Rampaging Ferocidon walk the same road with an upkeep drain or a self-damage rider attached; here the effect arrives clean, with no trigger to track and no cost to the aggressor. It is a creature and a lock occupying a single slot, one that closes the most common escape hatch while it swings.