Swarmyard Massacre

Create two 1/1 green Squirrel creature tokens. Then each creature that isn't an Insect, Rat, Spider, or Squirrel gets -1/-1 until end of turn for each creature you control that's an Insect, Rat, Spider, or Squirrel.

Dragonlair Spider

Reach
Whenever an opponent casts a spell, create a 1/1 green Insect creature token.

Hornet Nest

Defender (This creature can't attack.)
Whenever this creature is dealt damage, create that many 1/1 green Insect creature tokens with flying and deathtouch. (Any amount of damage a creature with deathtouch deals to a creature is enough to destroy it.)

Sakura-Tribe Elder

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

Moldervine Reclamation

Whenever a creature you control dies, you gain 1 life and draw a card.

Decimate

Destroy target artifact, target creature, target enchantment, and target land. (You can't cast this spell unless you have legal choices for all its targets.)

Braids, Arisen Nightmare

At the beginning of your end step, you may sacrifice an artifact, creature, enchantment, land, or planeswalker. If you do, each opponent may sacrifice a permanent of their choice that shares a card type with it. For each opponent who doesn't, that player loses 2 life and you draw a card.

Cinder Glade

({T}: Add {R} or {G}.)
This land enters tapped unless you control two or more basic lands.

Terminate

Destroy target creature. It can't be regenerated.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Broodhatch Nantuko

Whenever this creature is dealt damage, you may create that many 1/1 green Insect creature tokens.
Morph {2}{G} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Mazirek, Kraul Death Priest

Flying
Whenever a player sacrifices another permanent, put a +1/+1 counter on each creature you control.

Xira, the Golden Sting

Flying, haste
Whenever Xira 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.

Swarmyard

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

Sol Ring

Urabrask's Forge

At the beginning of combat on your turn, put an oil counter on this artifact, then create an X/1 red Phyrexian Horror creature token with trample and haste, where X is the number of oil counters on this artifact. Sacrifice that token at the beginning of the next end step.

Giant Adephage

Trample
Whenever this creature deals combat damage to a player, create a token that's a copy of this creature.

Mountain

Rockfall Vale

This land enters tapped unless you control two or more other lands.
{T}: Add {R} or {G}.

Aatchik, Emerald Radian

When Aatchik enters, create a 1/1 green Insect creature token for each artifact and/or creature card in your graveyard.
Whenever another Insect you control dies, put a +1/+1 counter on Aatchik. Each opponent loses 1 life.

Savage Lands

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

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Living Hive

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

Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

Hornet Queen

Flying, deathtouch
When this creature enters, create four 1/1 green Insect creature tokens with flying and deathtouch.

Skullclamp

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

Talisman of Resilience

{T}: Add {C}.
{T}: Add {B} or {G}. This artifact deals 1 damage to you.

Cultivate

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Grist, the Hunger Tide

As long as Grist isn't on the battlefield, it's a 1/1 Insect creature in addition to its other types.
+1: Create a 1/1 black and green Insect creature token, then mill a card. If an Insect card was milled this way, put a loyalty counter on Grist and repeat this process.
−2: You may sacrifice a creature. When you do, destroy target creature or planeswalker.
−5: Each opponent loses life equal to the number of creature cards in your graveyard.

Kodama's Reach

Morbid Opportunist

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

Rootbound Crag

This land enters tapped unless you control a Mountain or a Forest.
{T}: Add {R} or {G}.

Scute Mob

At the beginning of your upkeep, if you control five or more lands, put four +1/+1 counters on this creature.

Swamp

Devouring Swarm

Flying
Sacrifice a creature: This creature gets +1/+1 until end of turn.

Golgari Rot Farm

This land enters tapped.
When this land enters, return a land you control to its owner's hand.
{T}: Add {B}{G}.

The Swarmweaver

When The Swarmweaver enters, create two 1/1 black and green Insect creature tokens with flying.
Delirium — As long as there are four or more card types among cards in your graveyard, Insects and Spiders you control get +1/+1 and have deathtouch.

Fumulus, the Infestation

Flying, deathtouch
Whenever a player sacrifices a nontoken creature, create a 1/1 black Insect creature token with flying.
Whenever an Insect, Leech, Slug, or Worm you control attacks, defending player loses 1 life and you gain 1 life.

Victimize

Choose two target creature cards in your graveyard. Sacrifice a creature. If you do, return the chosen cards to the battlefield tapped.

Village Rites

As an additional cost to cast this spell, sacrifice a creature.
Draw two cards.

Command Tower

Beast Within

Destroy target permanent. Its controller creates a 3/3 green Beast creature token.

Smoldering Marsh

({T}: Add {B} or {R}.)
This land enters tapped unless you control two or more basic lands.

Nesting Dragon

Flying
Landfall — Whenever a land you control enters, create a 0/2 red Dragon Egg creature token with defender and "When this token dies, create a 2/2 red Dragon creature token with flying and '{R}: This token gets +1/+0 until end of turn.'"

Radiant Performer

Flash
When this creature enters, if you cast it from your hand, choose target spell or ability that targets only a single permanent or player. Copy that spell or ability for each other permanent or player the spell or ability could target. Each copy targets a different one of those permanents and players.

Putrefy

Destroy target artifact or creature. It can't be regenerated.

Llanowar Wastes

{T}: Add {C}.
{T}: Add {B} or {G}. This land deals 1 damage to you.

Woodland Cemetery

This land enters tapped unless you control a Swamp or a Forest.
{T}: Add {B} or {G}.

Vraska Joins Up

When Vraska Joins Up enters, put a deathtouch counter on each creature you control.
Whenever a legendary creature you control deals combat damage to a player, draw a card.

Icon of Ancestry

As this artifact enters, choose a creature type.
Creatures you control of the chosen type get +1/+1.
{3}, {T}: Look at the top three cards of your library. You may reveal a creature card of the chosen type from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Artifact Mutation

Destroy target artifact. It can't be regenerated. Create X 1/1 green Saproling creature tokens, where X is that artifact's mana value.

Terramorphic Expanse

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Farseek

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Bastion of Remembrance

When this enchantment enters, create a 1/1 white Human Soldier creature token.
Whenever a creature you control dies, each opponent loses 1 life and you gain 1 life.

Forest

Caustic Caterpillar

{1}{G}, Sacrifice this creature: Destroy target artifact or enchantment.

Arachnogenesis

Create X 1/2 green Spider creature tokens with reach, where X is the number of creatures attacking you. Prevent all combat damage that would be dealt this turn by non-Spider creatures.

Golgari Signet

Blood Artist

Whenever this creature or another creature dies, target player loses 1 life and you gain 1 life.

Haywire Mite

When this creature dies, you gain 2 life.
{G}, Sacrifice this creature: Exile target noncreature artifact or noncreature enchantment.

Seedship Agrarian

Whenever this creature becomes tapped, create a Lander token. (It's an artifact with "{2}, {T}, Sacrifice this token: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.")
Landfall — Whenever a land you control enters, put a +1/+1 counter on this creature.

Endless Cockroaches

When this creature dies, return it to its owner's hand.

Ant Queen

{1}{G}: Create a 1/1 green Insect creature token.

Riveteers Charm

Choose one —
• Target opponent sacrifices a creature or planeswalker they control with the greatest mana value among creatures and planeswalkers they control.
• Exile the top three cards of your library. Until your next end step, you may play those cards.
• Exile target player's graveyard.

Scute Swarm

Landfall — Whenever a land you control enters, create a 1/1 green Insect creature token. If you control six or more lands, create a token that's a copy of this creature instead.

Assassin's Trophy

Destroy target permanent an opponent controls. Its controller may search their library for a basic land card, put it onto the battlefield, then shuffle.

Dragonskull Summit

This land enters tapped unless you control a Swamp or a Mountain.
{T}: Add {B} or {R}.

Migration Path

Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.
Cycling {2} ({2}, Discard this card: Draw a card.)

Saber Ants

Whenever this creature is dealt damage, you may create that many 1/1 green Insect creature tokens.

Goblin Bombardment

Sacrifice a creature: This enchantment deals 1 damage to any target.

Corrupted Conviction

Rampant Growth

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

Izoni, Thousand-Eyed

Undergrowth — When Izoni enters, create a 1/1 black and green Insect creature token for each creature card in your graveyard.
{B}{G}, Sacrifice another creature: You gain 1 life and draw a card.

Path of Ancestry

This land enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Deadly Dispute

As an additional cost to cast this spell, sacrifice an artifact or creature.
Draw two cards and create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")