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.

Robber Fly

Flying
Whenever Robber Fly becomes blocked, defending player discards all the cards in their hand, then draws that many cards.

Swarm of Bloodflies

Flying
Swarm of Bloodflies enters with two +1/+1 counters on it.
Whenever another creature dies, put a +1/+1 counter on Swarm of Bloodflies.

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.)

Rotfeaster Maggot

When Rotfeaster Maggot enters, exile target creature card from a graveyard. You gain life equal to that card's toughness.

Ferropede

Ferropede can't be blocked.
Whenever Ferropede deals combat damage to a player, you may remove a counter from target permanent.

Bilious Skulldweller

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

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 Deadly Grub 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.)

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.

Death Charmer

Whenever Death Charmer deals combat damage to a creature, that creature's controller loses 2 life unless they pay {2}.

Skin Shedder

Skin Invasion

Enchant creature
Enchanted creature attacks each combat if able.
When enchanted creature dies, return Skin Invasion to the battlefield transformed under your control.

Skin Invasion // Skin Shedder

Dune Beetle

Kraul Raider

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

Bloatfly Swarm

Flying
Bloatfly Swarm enters 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.

Virus Beetle

When Virus Beetle enters, each opponent discards a card.

Pestilent Syphoner

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

Carrion Locust

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

Invader Parasite

Imprint — When Invader Parasite enters, exile target land.
Whenever a land an opponent controls with the same name as the exiled card enters, Invader Parasite deals 2 damage to that player.

Barbed Shocker

Trample, haste
Whenever Barbed Shocker deals damage to a player, that player discards all the cards in their hand, then draws that many cards.

Infesting Radroach

Flying
Infesting Radroach can't block.
Whenever Infesting Radroach deals combat damage to a player, they get that many rad counters.
Whenever an opponent mills a nonland card, if Infesting Radroach is in your graveyard, you may return it to your hand.

Spire Mangler

Flash
Flying
When Spire Mangler enters, target creature you control with flying gets +2/+0 until end of turn.

Shocker

Whenever Shocker deals damage to a player, that player discards all the cards in their hand, then draws that many cards.

Skittering Heartstopper

{B}: Skittering Heartstopper gains deathtouch until end of turn.

Necrosquito

Flying
Necrosquito enters with two oil counters on it.
Necrosquito gets +1/+1 for each oil counter on it.
Whenever another creature or artifact you control is put into a graveyard from the battlefield, put an oil counter on Necrosquito.

Spined Fluke

When Spined Fluke enters, sacrifice a creature.
{B}: Regenerate Spined Fluke.

Circuit Mender

When Circuit Mender enters, you gain 2 life.
When Circuit Mender leaves the battlefield, draw a card.

Skullslither Worm

When Skullslither Worm enters, each opponent discards a card. For each opponent who can't, put two +1/+1 counters on Skullslither Worm.

Ambush Gigapede

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

Mind Maggots

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