Cloakwood Swarmkeeper

Gathered Swarm — Whenever one or more tokens enter the battlefield under your control, put a +1/+1 counter on Cloakwood Swarmkeeper.

Hornet Sting

Hornet Sting deals 1 damage to any target.

Feed the Swarm

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

Peppersmoke

Target creature gets -1/-1 until end of turn. If you control a Faerie, draw a card.

Amzu, Swarm's Hunger

Flying, menace
Other Insects you control have menace.
Whenever one or more cards leave your graveyard, you may create a 1/1 black and green Insect creature token, then put a number of +1/+1 counters on it equal to the greatest mana value among those cards. Do this only once each turn.

Swamp

Bloatfly Swarm

Flying
Bloatfly Swarm enters the battlefield with five +1/+1 counters on it.
If damage would be dealt to Bloatfly Swarm while it has a +1/+1 counter on it, prevent that damage, remove that many +1/+1 counters from it, then give each player a rad counter for each +1/+1 counter removed this way.

Wirefly Hive

{3}, {T}: Flip a coin. If you win the flip, create a 2/2 colorless Insect artifact creature token with flying named Wirefly. If you lose the flip, destroy all permanents named Wirefly.

Hive of the Eye Tyrant

If you control two or more other lands, Hive of the Eye Tyrant enters the battlefield tapped.
{T}: Add {B}.
{3}{B}: Until end of turn, Hive of the Eye Tyrant becomes a 3/3 black Beholder creature with menace and "Whenever this creature attacks, exile target card from defending player's graveyard." It's still a land.

Hivestone

Creatures you control are Slivers in addition to their other creature types.

Death of a Thousand Stings

Target player loses 1 life and you gain 1 life.
At the beginning of your upkeep, if you have more cards in hand than each opponent, you may return Death of a Thousand Stings from your graveyard to your hand.

Hiveheart Shaman

Whenever Hiveheart Shaman attacks, you may search your library for a basic land card that doesn't share a land type with a land you control, put that card onto the battlefield, then shuffle.
{5}{G}: Create a 1/1 green Insect creature token. Put X +1/+1 counters on it, where X is the number of basic land types among lands you control. Activate only as a sorcery.

Unyaro Bee Sting

Unyaro Bee Sting deals 2 damage to any target.

Mountain

Lethal Sting

As an additional cost to cast this spell, put a -1/-1 counter on a creature you control.
Destroy target creature.

Bee Sting

Forest

Xira, the Golden Sting

Flying, haste
Whenever Xira, the Golden Sting attacks, put an egg counter on another target creature without an egg counter on it. When that creature dies, if it has an egg counter on it, draw a card and create a 1/1 black Insect creature token with flying.

Wirewood Hivemaster

Whenever another nontoken Elf enters the battlefield, you may create a 1/1 green Insect creature token.

Smoke

Players can't untap more than one creature during their untap steps.

Vraska, Swarm's Eminence

Whenever a creature you control with deathtouch deals damage to a player or planeswalker, put a +1/+1 counter on that creature.
−2: Create a 1/1 black Assassin creature token with deathtouch and "Whenever this creature deals damage to a planeswalker, destroy that planeswalker."

Unyaro Bees

Flying
{G}: Unyaro Bees gets +1/+1 until end of turn.
{3}{G}, Sacrifice Unyaro Bees: It deals 2 damage to any target.

Living Hive

Trample
Whenever Living Hive deals combat damage to a player, create that many 1/1 green Insect creature tokens.

Killer Bees

Flying
{G}: Killer Bees gets +1/+1 until end of turn.

Groundskeeper

{1}{G}: Return target basic land card from your graveyard to your hand.

Swarmyard

{T}: Add {C}.
{T}: Regenerate target Insect, Rat, Spider, or Squirrel. (The next time it would be destroyed, instead tap it, remove it from combat, and heal all damage on it.)

The Hive

{5}, {T}: Create a 1/1 colorless Insect artifact creature token with flying named Wasp. (It can't be blocked except by creatures with flying or reach.)

Stinging Study

You draw X cards and you lose X life, where X is the mana value of a commander you own on the battlefield or in the command zone.

Battlefly Swarm

Flying
{B}: Battlefly Swarm gains deathtouch until end of turn.

Stinging Hivemaster

Toxic 1 (Players dealt combat damage by this creature also get a poison counter.)
When Stinging Hivemaster dies, create a 1/1 colorless Phyrexian Mite artifact creature token with toxic 1 and "This creature can't block."

Aether Sting

Whenever an opponent casts a creature spell, Aether Sting deals 1 damage to that player.