Timberwatch Elf

Most lords flatten the tribe into a static buff: every Elf is bigger all the time, and the math is settled before you draw the card. This one converts board presence into a one-shot pump that scales with the whole battlefield's Elf count, then funnels all of it into a single creature. On a wide Elf board built around mana dorks, Wirewood Herald, Wellwisher, and a dozen one-drops, the ability stops being a small edge and becomes the reach the deck otherwise lacks: tap it and a modest body suddenly outclasses anything in front of it, winning the combat it picks and trading up against blockers it could never have touched. The toughness half of +X/+X matters as much as the power, letting the chosen attacker survive a block or sit back as a wall that nothing on the other side can profitably crash into. What it pays for that ceiling is fragility and tempo: a 1/2 frame that wants the board already deployed, an ability locked behind summoning sickness, and a payoff that shrinks the moment removal trims the count before you tap. It is also a single target, so it answers one threat or pushes one attacker, not a sweeper aimed at everything. The deal is the same one Elf decks are always making: idle when the board is bare, lethal when it is crowded.