Endless Cockroaches

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

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.

Wriggling Grub

When this creature dies, create two 1/1 black and green Worm creature tokens.

Battlefly Swarm

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

Infestation Sage

When this creature dies, create a 1/1 black and green Insect creature token with flying.

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.

Ayara, First of Locthwain

Whenever Ayara or another black creature you control enters, each opponent loses 1 life and you gain 1 life.
{T}, Sacrifice another black creature: Draw a card.

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.

Mortician Beetle

Whenever a player sacrifices a creature, you may put a +1/+1 counter on this creature.

Mole Worms

You may choose not to untap this creature during your untap step.
{T}: Tap target land. It doesn't untap during its controller's untap step for as long as this creature remains tapped.