Marauding Blight-Priest

Whenever you gain life, each opponent loses 1 life.

Environmental Sciences

Search your library for a basic land card, reveal it, put it into your hand, then shuffle. You gain 2 life.

Forest

Revitalize

Sprout Swarm

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Buyback {3} (You may pay an additional {3} as you cast this spell. If you do, put this card into your hand as it resolves.)
Create a 1/1 green Saproling creature token.

Pest Summoning

Create two 1/1 black and green Pest creature tokens with "When this creature dies, you gain 1 life."

Lampad of Death's Vigil

{1}, Sacrifice a creature: Each opponent loses 1 life and you gain 1 life.

Plains

Blood Researcher

Menace (This creature can't be blocked except by two or more creatures.)
Whenever you gain life, put a +1/+1 counter on Blood Researcher.

Introduction to Prophecy

Scoured Barrens

Scoured Barrens enters tapped.
When Scoured Barrens enters, you gain 1 life.
{T}: Add {W} or {B}.

Swamp

Radiant Fountain

When Radiant Fountain enters, you gain 2 life.
{T}: Add {C}.

Charge

Creatures you control get +1/+1 until end of turn.

Deathbloom Thallid

When Deathbloom Thallid dies, create a 1/1 green Saproling creature token.

Tukatongue Thallid

When Tukatongue Thallid dies, create a 1/1 green Saproling creature token.

Hunt for Specimens

Create a 1/1 black and green Pest creature token with "When this creature dies, you gain 1 life."
Learn. (You may reveal a Lesson card you own from outside the game and put it into your hand, or discard a card to draw a card.)

Fungal Infection

Target creature gets -1/-1 until end of turn. Create a 1/1 green Saproling creature token.

Plagued Rusalka

{B}, Sacrifice a creature: Target creature gets -1/-1 until end of turn.

Cram Session

You gain 4 life.
Learn. (You may reveal a Lesson card you own from outside the game and put it into your hand, or discard a card to draw a card.)

Infuse with Vitality

Until end of turn, target creature gains deathtouch and "When this creature dies, return it to the battlefield tapped under its owner's control."
You gain 2 life.

Blossoming Sands

Blossoming Sands enters tapped.
When Blossoming Sands enters, you gain 1 life.
{T}: Add {G} or {W}.

Jungle Hollow

Jungle Hollow enters tapped.
When Jungle Hollow enters, you gain 1 life.
{T}: Add {B} or {G}.

Professor of Zoomancy

When Professor of Zoomancy enters, create a 1/1 black and green Pest creature token with "When this creature dies, you gain 1 life."