Read the Bones

Scry 2, then draw two cards. You lose 2 life. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Jungle Hollow

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {B} or {G}.

Sign in Blood

Target player draws two cards and loses 2 life.

Roots of Wisdom

Mill three cards, then return a land card or Elf card from your graveyard to your hand. If you can't, draw a card. (To mill a card, put the top card of your library into your graveyard.)

Elves of Deep Shadow

{T}: Add {B}. Elves of Deep Shadow deals 1 damage to you.

Swamp

Phyrexian Rager

When Phyrexian Rager enters, you draw a card and you lose 1 life.

Gladecover Scout

Hexproof (This creature can't be the target of spells or abilities your opponents control.)

Vendetta

Destroy target nonblack creature. It can't be regenerated. You lose life equal to that creature's toughness.

Llanowar Elves

Jaspera Sentinel

Reach
{T}, Tap an untapped creature you control: Add one mana of any color.

Gilt-Leaf Ambush

Create two 1/1 green Elf Warrior creature tokens. Clash with an opponent. If you win, those creatures gain deathtouch until end of turn. (Each clashing player reveals the top card of their library, then puts that card on the top or bottom. A player wins if their card had a higher mana value. Any amount of damage a creature with deathtouch deals to a creature is enough to destroy it.)

Fyndhorn Elves

Forest

Eyeblight Cullers

When Eyeblight Cullers dies, create three 1/1 green Elf Warrior creature tokens, then mill three cards. (Put the top three cards of your library into your graveyard.)

Eyeblight's Ending

Golgari Rot Farm

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

Wrap in Vigor

Feed the Swarm

Destroy target creature or enchantment an opponent controls. You lose life equal to that permanent's mana value.

Gray Merchant of Asphodel

When Gray Merchant of Asphodel enters, each opponent loses X life, where X is your devotion to black. You gain life equal to the life lost this way. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)

Lys Alana Huntmaster

Whenever you cast an Elf spell, you may create a 1/1 green Elf Warrior creature token.

Disciple of Phenax

When Disciple of Phenax enters, target player reveals a number of cards from their hand equal to your devotion to black. You choose one of them. That player discards that card. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)

Elvish Guidance

Enchant land
Whenever enchanted land is tapped for mana, its controller adds an additional {G} for each Elf on the battlefield.

Elvish Visionary

When Elvish Visionary enters, draw a card.

Blood-Toll Harpy

Flying
When Blood-Toll Harpy enters, each player loses 1 life.

Crashing Drawbridge

Defender
{T}: Creatures you control gain haste until end of turn.

Elvish Mystic

Arbor Elf

Child of Night

Baleful Eidolon

Bestow {4}{B} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached to a creature.)
Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Enchanted creature gets +1/+1 and has deathtouch.

Bloodflow Connoisseur

Sacrifice a creature: Put a +1/+1 counter on Bloodflow Connoisseur.

Timberwatch Elf

{T}: Target creature gets +X/+X until end of turn, where X is the number of Elves on the battlefield.