Azula Always Lies

Choose one or both —
• Target creature gets -1/-1 until end of turn.
• Put a +1/+1 counter on target creature.

Feed the Swarm

Destroy target creature or enchantment an opponent controls. You lose life equal to that permanent's mana value.

Buzzard-Wasp Colony

Flying
When this creature enters, you may sacrifice an artifact or creature. If you do, draw a card.
Whenever another creature you control dies, if it had counters on it, put its counters on this creature.

Fire Nation Sentinels

Whenever a nontoken creature an opponent controls dies, put a +1/+1 counter on each creature you control.

Elephant-Rat

Menace (This creature can't be blocked except by two or more creatures.)

Swamp

Ozai's Cruelty

Ozai's Cruelty deals 2 damage to target player. That player discards two cards.

Earth Village Ruffians

When this creature dies, earthbend 2. (Target land you control becomes a 0/0 creature with haste that's still a land. Put two +1/+1 counters on it. When it dies or is exiled, return it to the battlefield tapped.)

Gilacorn

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)

Hog-Monkey

At the beginning of combat on your turn, target creature you control with a +1/+1 counter on it gains menace until end of turn. (It can't be blocked except by two or more creatures.)
Exhaust — {5}: Put two +1/+1 counters on this creature. (Activate each exhaust ability only once.)

Counters

Long Feng, Grand Secretariat

Whenever another creature you control or a land you control is put into a graveyard from the battlefield, put a +1/+1 counter on target creature you control.

Thriving Moor

This land enters tapped. As it enters, choose a color other than black.
{T}: Add {B} or one mana of the chosen color.

Fire Nation Engineer

Raid — At the beginning of your end step, if you attacked this turn, put a +1/+1 counter on another target creature or Vehicle you control.

Dai Li Indoctrination

Choose one —
• Target opponent reveals their hand. You choose a nonland permanent card from it. That player discards that card.
• Earthbend 2. (Target land you control becomes a 0/0 creature with haste that's still a land. Put two +1/+1 counters on it. When it dies or is exiled, return it to the battlefield tapped.)