Turn Stones

For each opponent, you create a 1/1 black and green Pest creature token with "When this token dies, you gain 1 life."

Eccentric Pestfinder

Trample
At the beginning of each end step, if you gained life this turn, this creature becomes prepared. (While it's prepared, you may cast a copy of its spell. Doing so unprepares it.)

Eccentric Pestfinder // Turn Stones

Pest Friend

Create a 1/1 black and green Pest creature token with "Whenever this token attacks, you gain 1 life."

Lluwen, Exchange Student

Lluwen enters prepared. (While it's prepared, you may cast a copy of its spell. Doing so unprepares it.)
Exile a creature card from your graveyard: Lluwen becomes prepared. Activate only as a sorcery.

Lluwen, Exchange Student // Pest Friend

Blech, Loafing Pest

Whenever you gain life, put a +1/+1 counter on each Pest, Bat, Insect, Snake, and Spider you control.

Search for Blex

Look at the top five cards of your library. You may put any number of them into your hand and the rest into your graveyard. You lose 3 life for each card you put into your hand this way.

Blex, Vexing Pest

Other Pests, Bats, Insects, Snakes, and Spiders you control get +1/+1.
When Blex dies, you gain 4 life.

Blex, Vexing Pest // Search for Blex

Teacher's Pest

Menace (This creature can't be blocked except by two or more creatures.)
Whenever this creature attacks, you gain 1 life.
{B}{G}: Return this card from your graveyard to the battlefield tapped.