Have

Caustic Crawler

Landfall — Whenever a land you control enters, you may have target creature get -1/-1 until end of turn.

Ironshell Beetle

When this creature enters, put a +1/+1 counter on target creature.

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.

Giant Cockroach

Dune Beetle

Skittering Heartstopper

{B}: This creature gains deathtouch until end of turn.

Living Hive

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

Carrion Beetles

{2}{B}, {T}: Exile up to three target cards from a single graveyard.

Endless Cockroaches

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

Fog of Gnats

Spider Spawning

Create a 1/2 green Spider creature token with reach for each creature card in your graveyard.
Flashback {6}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Invasive Species

When this creature enters, return another permanent you control to its owner's hand.

Quarry Beetle

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

Fretwork Colony

This creature can't block.
At the beginning of your upkeep, put a +1/+1 counter on this creature and you lose 1 life.

Coiling Woodworm

Coiling Woodworm's power is equal to the number of Forests on the battlefield.

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.)

Hawkeater Moth

Flying
Shroud (This creature can't be the target of spells or abilities.)

Durable Coilbug

{4}{B}: Return this card from your graveyard to your hand.

Locust Swarm

Flying
{G}: Regenerate this creature.
{G}: Untap this creature. Activate only once each turn.

Giant Dustwasp

Flying
Suspend 4—{1}{G} (Rather than cast this card from your hand, you may pay {1}{G} and exile it with four time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost. It has haste.)

Huskburster Swarm

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

Brain Maggot

When this creature enters, target opponent reveals their hand and you choose a nonland card from it. Exile that card until this creature leaves the battlefield.

Colossapede

Battlefly Swarm

Flying
{B}: This creature gains deathtouch until end of turn.

Plague Fiend

Whenever this creature deals combat damage to a creature, destroy that creature unless its controller pays {2}.

Viridescent Bog

Carrion Grub

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

Goliath Beetle

Spineseeker Centipede

When this creature enters, search your library for a basic land card, reveal it, put it into your hand, then shuffle.
Delirium — This creature gets +1/+2 and has vigilance as long as there are four or more card types among cards in your graveyard.

Basic Land

Swamp

Jagwasp Swarm

Xantid Swarm

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

Carrion Locust

Flying
When this creature enters, exile target card from an opponent's graveyard. If it was a creature card, that player loses 1 life.

Crash of Rhino Beetles

Trample
This creature gets +10/+10 as long as you control ten or more lands.

Heartstabber Mosquito

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

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.

Devouring Swarm

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

Deadly Insect

Shroud (This creature can't be the target of spells or abilities.)

Swarm of Bloodflies

Flying
This creature enters with two +1/+1 counters on it.
Whenever another creature dies, put a +1/+1 counter on this creature.

Gleancrawler

({B/G} can be paid with either {B} or {G}.)
Trample
At the beginning of your end step, return to your hand all creature cards in your graveyard that were put there from the battlefield this turn.

Caustic Wasps

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

Flesh Burrower

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

Forest

Mind Maggots

When this creature enters, discard any number of creature cards. For each card discarded this way, put two +1/+1 counters on this creature.

Duskshell Crawler

When this creature enters, put a +1/+1 counter on target creature.
Each creature you control with a +1/+1 counter on it has trample. (It can deal excess combat damage to the player or planeswalker it's attacking.)

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 this creature is turned face up, all creatures get -X/-X until end of turn.

Giant Ladybug

Reach
When this creature enters, you may search your library for a basic land card, reveal it, then shuffle and put that card on top.

Caustic Caterpillar

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

Delta Bloodflies

Flying
Whenever this creature attacks, if you control a creature with a counter on it, each opponent loses 1 life.

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}.)

Foundry Hornet

Flying
When this creature enters, if you control a creature with a +1/+1 counter on it, creatures your opponents control get -1/-1 until end of turn.

Getting

Decimator Beetle

When this creature enters, put a -1/-1 counter on target creature you control.
Whenever this creature attacks, remove a -1/-1 counter from target creature you control and put a -1/-1 counter on up to one target creature defending player controls.

Life from the Loam

Return up to three target land cards from your graveyard to your hand.
Dredge 3 (If you would draw a card, you may mill three cards instead. If you do, return this card from your graveyard to your hand.)

Carrion Ants

{1}: This creature gets +1/+1 until end of turn.

Moldgraf Millipede

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

Giant Mantis

Reach (This creature can block creatures with flying.)

Dross Hopper

Sacrifice a creature: This creature gains flying until end of turn.

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 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

Giant Caterpillar

{G}, Sacrifice this creature: Create a 1/1 green Insect creature token with flying named Butterfly at the beginning of the next end step.

Bayou Dragonfly

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

Ambush Gigapede

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

Emerald Dragonfly

Flying
{G}{G}: This creature gains first strike until end of turn.

Krotiq Nestguard

Defender
{2}{G}: This creature can attack this turn as though it didn't have defender.

Blister Beetle

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

Deadbridge Goliath

Scavenge {4}{G}{G} ({4}{G}{G}, Exile this card from your graveyard: Put a number of +1/+1 counters equal to this card's power on target creature. Scavenge only as a sorcery.)

Bond Beetle

Pincher Beetles

Giant Ankheg

Trample
Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
Other creatures you control have trample and ward {2}.

Gigapede

Shroud (This creature can't be the target of spells or abilities.)
At the beginning of your upkeep, if this card is in your graveyard, you may discard a card. If you do, return this card to your hand.

Twilight Mire

{T}: Add {C}.
{B/G}, {T}: Add {B}{B}, {B}{G}, or {G}{G}.

Loam Larva

When this creature enters, you may search your library for a basic land card, reveal it, then shuffle and put that card on top.

Nessian Hornbeetle

At the beginning of combat on your turn, if you control another creature with power 4 or greater, put a +1/+1 counter on this creature.

Drudge Beetle

Scavenge {5}{G} ({5}{G}, Exile this card from your graveyard: Put a number of +1/+1 counters equal to this card's power on target creature. Scavenge only as a sorcery.)

Woodland Cemetery

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

Hornet Queen

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

Brain Weevil

Intimidate (This creature can't be blocked except by artifact creatures and/or creatures that share a color with it.)
Sacrifice this creature: Target player discards two cards. Activate only as a sorcery.

Adaptive Shimmerer

Flash
This creature enters with three +1/+1 counters on it.

Deadly Grub

Vanishing 3 (This creature enters with three time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
When this creature dies, if it had no time counters on it, create a 6/1 green Insect creature token with shroud. (It can't be the target of spells or abilities.)

Kazandu Nectarpot

Landfall — Whenever a land you control enters, you gain 1 life.

Iridescent Hornbeetle

At the beginning of your end step, create a 1/1 green Insect creature token for each +1/+1 counter you've put on creatures under your control this turn.

Brood of Cockroaches

When this creature is put into your graveyard from the battlefield, at the beginning of the next end step, you lose 1 life and return this card to your hand.

Ant Queen

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

Giant Adephage

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

Blightbeetle

Protection from green (This creature can't be blocked, targeted, dealt damage, enchanted, or equipped by anything green.)
Creatures your opponents control can't have +1/+1 counters put on them.

Flow of Maggots

Cumulative upkeep {1} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
This creature can't be blocked by non-Wall creatures.

Grave-Shell Scarab

{1}, Sacrifice this creature: Draw a card.
Dredge 1 (If you would draw a card, you may mill a card instead. If you do, return this card from your graveyard to your hand.)