Abzan Kin-Guard

A four-mana 3/3 that carries a keyword belonging to its wedge-mates, gated behind a condition soft enough to almost always be met. The lifelink is white-and-black flavor grafted onto a green body: you have it whenever you control a white or black permanent, which is to say whenever the deck around it is the three-color midrange shell it was designed for. The grant is a static ability keyed to your board, not a spell or a trigger, so it ignores timing entirely: a white or black creature, enchantment, or planeswalker sitting in play keeps the keyword live turn after turn, no upkeep tax, no restacking. And because the ability checks the game state continuously, the lifelink flickers off the moment that permanent leaves and back on the moment another arrives, without anyone doing anything. One wrinkle worth knowing: basic lands are colorless, so a Plains or a Swamp on its own does not satisfy the clause; the ability wants a genuinely white or black object. That makes the keyword durable in practice while remaining technically conditional, the gentlest tax a card can charge for a cross-color reward. Underneath, it is a common-rarity payoff for committing to the wedge in deckbuilding: the floor is a competent beater that fills a curve without asking for anything, and the ceiling is incidental life on every swing and block once the rest of the colors show up. It never demands you build around it, which is exactly the point of a common. It quietly rewards you for having done so.