Smog Elemental

A flier that hates other fliers, which is a sharper piece of color-pie work than it looks. Black does not usually get to police the air; that has historically been white's job (the Serra-style anthem-against, the Hushwing-style hatebear) or green's (reach). This card hands black a self-contained answer that operates on the dimension black is weakest at. The -1/-1 to opposing fliers is a passive sweep, not a targeted one: it kills X/1 evasive bodies on sight, shrinks the rest below combat math, and survives the board state rather than spending itself the way a removal spell would. The asymmetry matters too, since the penalty hits only what opponents control, so it leaves a black flier corps untouched while quietly clearing the skies above it. The 3/3 frame keeps the package honest, since at six mana it does not also dominate the ground; you are paying for the static effect and getting a serviceable evasive body attached rather than the reverse. The design idea is the durable part here: a continuous anti-evasion enchantment-on-a-stick stapled to a creature that itself flies, so the thing enforcing the rule also benefits from breaking the opposition under it.