Savage Gorger

The trigger's condition is looser than the body suggests: any life loss by any opponent, from any source, at any point in the turn, satisfies it. The Vampire does not have to connect in combat, does not have to be the one dealing the damage, and does not care whether the loss came from a burn spell, a drain effect, another attacker, or an opposing fetchland payment. Its flying helps start the process, but once a black deck is grinding a life total down by other means, this creature banks its growth for free at your end step no matter what it did that turn. That decoupling of the reward from the body's own combat is the design idea: a 1/1 flier that snowballs off the deck's aggregate pressure rather than its personal contribution, so it rewards a board built to bleed rather than a single hard-hitting threat. The check fires once on your end step and pays exactly one counter, so it does not matter whether the opponent lost one point or twenty; the size grows a step per turn the condition is met, and the counters are permanent, so a game the opponent survives still leaves the Vampire larger for having been there. The limit is fragility: three mana buys a 1/1 that invites removal before the engine ever compounds, and a single answer erases every counter it has earned.