Vitality Hunter

Lifelink counters are the reason this creature exists: it treats a keyword usually kept static and personal as a portable resource to distribute across a board. Monstrosity is the delivery mechanism, and the coupling is where the design earns its keep. Pay a large X and you both inflate the body with X counters and hand lifelink to up to X target creatures in the same activation, converting a full team into a sustained life engine on the next combat. Because monstrosity is a one-time switch (a creature can only become monstrous once), the distribution is a single big payoff rather than a repeatable faucet, which keeps the effect from spiraling and pushes you to hold until the mana and the board are both present before committing to the full X. The counter framing is the durable part: because lifelink is granted as a physical counter rather than an aura or a continuous effect, the grant outlives its source. Kill this after it goes monstrous and the counters stay exactly where you placed them, still feeding your team long after the enabler is gone. A 3/4 with native lifelink is a serviceable body, but everything worth building around lives in that activation: the moment mana meets a wide board, and every creature you control starts trading blows for life.