Corpsejack Menace

If one or more +1/+1 counters would be put on a creature you control, twice that many +1/+1 counters are put on it instead.

Mirkwood Bats

Flying
Whenever you create or sacrifice a token, each opponent loses 1 life.

Llanowar Elves

Harbinger of Night

At the beginning of your upkeep, put a -1/-1 counter on each creature.

Maha, Its Feathers Night

Flying, trample
Ward—Discard a card.
Creatures your opponents control have base toughness 1.

Illness in the Ranks

Morbid Opportunist

Whenever one or more other creatures die, draw a card. This ability triggers only once each turn.

Golgari Charm

Choose one —
• All creatures get -1/-1 until end of turn.
• Destroy target enchantment.
• Regenerate each creature you control.

Old-Growth Grove

This land enters tapped.
{T}: Add {B} or {G}.

Revitalizing Repast

Put a +1/+1 counter on target creature. It gains indestructible until end of turn.

Revitalizing Repast // Old-Growth Grove

Skullclamp

Equipped creature gets +1/-1.
Whenever equipped creature dies, draw two cards.
Equip {1}

Massacre Girl, Known Killer

Menace
Creatures you control have wither. (They deal damage to creatures in the form of -1/-1 counters.)
Whenever a creature an opponent controls dies, if its toughness was less than 1, draw a card.

Genesis Chamber

Whenever a nontoken creature enters, if this artifact is untapped, that creature's controller creates a 1/1 colorless Myr artifact creature token.

Black Sun's Zenith

Put X -1/-1 counters on each creature. Shuffle Black Sun's Zenith into its owner's library.

Grismold, the Dreadsower

Trample
At the beginning of your end step, each player creates a 1/1 green Plant creature token.
Whenever a creature token dies, put a +1/+1 counter on Grismold.

Kaervek, the Spiteful

Sakura-Tribe Elder

Sacrifice this creature: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Virulent Plague

Plague Engineer

Deathtouch
As this creature enters, choose a creature type.
Creatures of the chosen type your opponents control get -1/-1.

Massacre Girl

Menace
When Massacre Girl enters, each other creature gets -1/-1 until end of turn. Whenever a creature dies this turn, each creature other than Massacre Girl gets -1/-1 until end of turn.

Species Specialist

As this creature enters, choose a creature type.
Whenever a creature of the chosen type dies, you may draw a card.