Nameless Inversion

Changeling (This card is every creature type.)
Target creature gets +3/-3 and loses all creature types until end of turn.

Bilious Skulldweller

Deathtouch
Toxic 1 (Players dealt combat damage by this creature also get a poison counter.)

Riveteers Overlook

When Riveteers Overlook enters, sacrifice it. When you do, search your library for a basic Swamp, Mountain, or Forest card, put it onto the battlefield tapped, then shuffle and you gain 1 life.

Evolving Wilds

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

Plague Stinger

Flying
Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Ambush Gigapede

Flash
When Ambush Gigapede enters, target creature an opponent controls gets -2/-2 until end of turn.

Nullmage Advocate

{T}: Return two target cards from an opponent's graveyard to their hand. Destroy target artifact or enchantment.

Forest

Buried Alive

Search your library for up to three creature cards, put them into your graveyard, then shuffle.

Forever Young

Put any number of target creature cards from your graveyard on top of your library.
Draw a card.

Nantuko Calmer

{G}, {T}, Sacrifice Nantuko Calmer: Destroy target enchantment.
Threshold — Nantuko Calmer gets +1/+1 as long as seven or more cards are in your graveyard.

Stinging Cave Crawler

Deathtouch
Descend 4 — Whenever Stinging Cave Crawler attacks, if there are four or more permanent cards in your graveyard, you draw a card and you lose 1 life.

Hornet Nest

Defender (This creature can't attack.)
Whenever Hornet Nest 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.)

Giant Adephage

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

Dross Hopper

Sacrifice a creature: Dross Hopper gains flying until end of turn.

Swamp

It of the Horrid Swarm

Emerge {6}{G} (You may cast this spell by sacrificing a creature and paying the emerge cost reduced by that creature's mana value.)
When you cast this spell, create two 1/1 green Insect creature tokens.

Pestilent Syphoner

Flying
Toxic 1 (Players dealt combat damage by this creature also get a poison counter.)

Huskburster Swarm

This spell costs {1} less to cast for each creature card you own in exile and in your graveyard.
Menace, deathtouch

Acridian

Echo {1}{G} (At the beginning of your upkeep, if this came under your control since the beginning of your last upkeep, sacrifice it unless you pay its echo cost.)

Caustic Wasps

Flying
Whenever Caustic Wasps deals combat damage to a player, you may destroy target artifact that player controls.

Altar of Dementia

Sacrifice a creature: Target player mills cards equal to the sacrificed creature's power.

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 Scute Swarm instead.

Arcbound Stinger

Flying
Modular 1 (This creature enters with a +1/+1 counter on it. When it dies, you may put its +1/+1 counters on target artifact creature.)

Xantid Swarm

Flying
Whenever Xantid Swarm attacks, defending player can't cast spells this turn.

Hornet Queen

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

Quarry Beetle

When Quarry Beetle enters, you may return target land card from your graveyard to the battlefield.

Caustic Caterpillar

{1}{G}, Sacrifice Caustic Caterpillar: Destroy target artifact or enchantment.

Village Rites

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

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.

Brass Gnat

Flying
Brass Gnat doesn't untap during your untap step.
At the beginning of your upkeep, you may pay {1}. If you do, untap Brass Gnat.

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.

Nantuko Elder

Carrion Grub

Carrion Grub gets +X/+0, where X is the greatest power among creature cards in your graveyard.
When Carrion Grub enters, mill four cards. (Put the top four cards of your library into your graveyard.)

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.)

Crawling Sensation

At the beginning of your upkeep, you may mill two cards. (You may put the top two cards of your library into your graveyard.)
Whenever one or more land cards are put into your graveyard from anywhere for the first time each turn, create a 1/1 green Insect creature token.

Broodspinner

Reach
When Broodspinner enters, surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)
{4}{B}{G}, {T}, Sacrifice Broodspinner: Create a number of 1/1 black and green Insect creature tokens with flying equal to the number of card types among cards in your graveyard.

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.

Altanak, the Thrice-Called

Trample
Whenever Altanak, the Thrice-Called becomes the target of a spell or ability an opponent controls, draw a card.
{1}{G}, Discard Altanak, the Thrice-Called: Return target land card from your graveyard to the battlefield tapped.

Myriad Landscape

Myriad Landscape enters tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice Myriad Landscape: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Halo Scarab

{2}, Exile Halo Scarab from your graveyard: Create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Emerald Dragonfly

Flying
{G}{G}: Emerald Dragonfly gains first strike until end of turn.

Command Tower

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

Canoptek Scarab Swarm

Flying
Feeder Mandibles — When Canoptek Scarab Swarm enters, exile target player's graveyard. For each artifact or land card exiled this way, create a 1/1 colorless Insect artifact creature token with flying.

Durable Coilbug

{4}{B}: Return Durable Coilbug from your graveyard to your hand.

Primordial Gnawer

When Primordial Gnawer dies, discover 3. (Exile cards from the top of your library until you exile a nonland card with mana value 3 or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)

Broodhatch Nantuko

Whenever Broodhatch Nantuko 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.)

Stirge

Flying
Stirge can't block.
Blood Drain — {1}{B}, Pay 1 life, Sacrifice Stirge: Draw a card.

Saber Ants

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

Battlefly Swarm

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

Devouring Swarm

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

Flesh Burrower

Deathtouch
Whenever Flesh Burrower attacks, another target creature you control gains deathtouch until end of turn.

Moldgraf Millipede

When Moldgraf Millipede enters, mill three cards, then put a +1/+1 counter on Moldgraf Millipede for each creature card in your graveyard. (To mill three cards, put the top three cards of your library into your graveyard.)

Bayou Dragonfly

Flying; swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)

Heartstabber Mosquito

Kicker {2}{B} (You may pay an additional {2}{B} as you cast this spell.)
Flying
When Heartstabber Mosquito enters, if it was kicked, destroy target creature.

Haywire Mite

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

Scute Mob

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

Kraul Foragers

Undergrowth — When Kraul Foragers enters, you gain 1 life for each creature card in your graveyard.

Crawling Infestation

At the beginning of your upkeep, you may mill two cards. (You may put the top two cards of your library into your graveyard.)
Whenever one or more creature cards are put into your graveyard from anywhere during your turn, create a 1/1 green Insect creature token. This ability triggers only once each turn.

Bane of the Living

Morph {X}{B}{B} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)
When Bane of the Living is turned face up, all creatures get -X/-X until end of turn.

Zask, Skittering Swarmlord

You may play lands and cast Insect spells from your graveyard.
Whenever another Insect you control dies, put it on the bottom of its owner's library, then mill two cards. (Put the top two cards of your library into your graveyard.)
{1}{B/G}: Target Insect gets +1/+0 and gains deathtouch until end of turn. ({B/G} can be paid with either {B} or {G}.)

Terramorphic Expanse

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

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.

Ambush Krotiq

Trample
When Ambush Krotiq enters, return another creature you control to its owner's hand.

Marker Beetles

When Marker Beetles dies, target creature gets +1/+1 until end of turn.
{2}, Sacrifice Marker Beetles: Draw a card.

Blister Beetle

When Blister Beetle enters, target creature gets -1/-1 until end of turn.

Ant Queen

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

Formless Genesis

Changeling (This card is every creature type.)
Create an X/X colorless Shapeshifter creature token with changeling and deathtouch, where X is the number of land cards in your graveyard.
Retrace (You may cast this card from your graveyard by discarding a land card in addition to paying its other costs.)

Grist, the Hunger Tide

As long as Grist, the Hunger Tide 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.

Realmwalker

Changeling (This card is every creature type.)
As Realmwalker enters, choose a creature type.
You may look at the top card of your library any time.
You may cast creature spells of the chosen type from the top of your library.

Skylasher

Flash
This spell can't be countered.
Reach, protection from blue

Grist, the Plague Swarm

+1: Create a 1/1 black and green Insect creature token, then mill two cards. Put a deathtouch counter on the token if a black card was milled this way.
−2: Destroy target artifact or enchantment.
−6: For each creature card in your graveyard, create a token that's a copy of it, except it's a 1/1 black and green Insect.

Grist, Voracious Larva

Deathtouch
Whenever Grist, Voracious Larva or another creature you control enters, if it entered from your graveyard or you cast it from your graveyard, you may pay {G}. If you do, exile Grist, then return it to the battlefield transformed under its owner's control.

Grist, Voracious Larva // Grist, the Plague Swarm

Graveshifter

Changeling (This card is every creature type.)
When Graveshifter enters, you may return target creature card from your graveyard to your hand.

Necropede

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
When Necropede dies, you may put a -1/-1 counter on target creature.