Creatures you control get +2/+2 until end of turn. Whenever a creature blocks this turn, its controller gets a poison counter.

Flying

When Noxious Dragon dies, you may destroy target creature with mana value 3 or less.

Menace

When Noxious Gearhulk enters the battlefield, you may destroy another target creature. If a creature is destroyed this way, you gain life equal to its toughness.

Destroy target creature or planeswalker that's green or white. You gain 1 life.

Noxious Hatchling enters the battlefield with four -1/-1 counters on it.

Wither (This deals damage to creatures in the form of -1/-1 counters.)

Whenever you cast a black spell, remove a -1/-1 counter from Noxious Hatchling.

Whenever you cast a green spell, remove a -1/-1 counter from Noxious Hatchling.

When Noxious Toad dies, each opponent discards a card.