Duskshell Crawler

When Duskshell Crawler 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.)

Giant Adephage

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

Battlefly Swarm

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

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.)

Ant Queen

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

Flesh Burrower

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

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.

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.

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.

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.

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.