Drain the Well

Golgari Rot Farm

This land enters tapped.
When this land enters, return a land you control to its owner's hand.
{T}: Add {B}{G}.

Forest

Entropic Eidolon

{B}, Sacrifice this creature: Target player loses 1 life and you gain 1 life.
Whenever you cast a multicolored spell, you may return this card from your graveyard to your hand.

Expanded Anatomy

Put two +1/+1 counters on target creature. It gains vigilance until end of turn.

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 this creature.

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.)

Pest Summoning

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

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.

Shambling Shell

Sacrifice this creature: Put a +1/+1 counter on target creature.
Dredge 3 (If you would draw a card, you may mill three cards instead. If you do, return this card from your graveyard to your hand.)

Odious Trow

Gift of the Deity

Enchant creature
As long as enchanted creature is black, it gets +1/+1 and has deathtouch. (Any amount of damage it deals to a creature is enough to destroy that creature.)
As long as enchanted creature is green, it gets +1/+1 and all creatures able to block it do so.

Swamp

Verdant Eidolon

{G}, Sacrifice this creature: Add three mana of any one color.
Whenever you cast a multicolored spell, you may return this card from your graveyard to your hand.