Llanowar Elves

Shelob, Dread Weaver

Whenever a nontoken creature an opponent controls dies, exile it.
{2}{B}, Put a creature card exiled with Shelob into its owner's graveyard: Put two +1/+1 counters on Shelob. Draw a card.
{X}{1}{B}: Put target creature card with mana value X exiled with Shelob onto the battlefield tapped under your control.

Mirkwood Spider

Deathtouch
Whenever this creature attacks, target legendary creature you control gains deathtouch until end of turn.

Overwhelming Stampede

Until end of turn, creatures you control gain trample and get +X/+X, where X is the greatest power among creatures you control.

Deathcap Glade

This land enters tapped unless you control two or more other lands.
{T}: Add {B} or {G}.

Fynn, the Fangbearer

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Whenever a creature you control with deathtouch deals combat damage to a player, that player gets two poison counters. (A player with ten or more poison counters loses the game.)

Arachnogenesis

Create X 1/2 green Spider creature tokens with reach, where X is the number of creatures attacking you. Prevent all combat damage that would be dealt this turn by non-Spider creatures.

Watcher in the Web

Reach (This creature can block creatures with flying.)
This creature can block an additional seven creatures each combat.

Sign in Blood

Target player draws two cards and loses 2 life.

Assault Formation

Each creature you control assigns combat damage equal to its toughness rather than its power.
{G}: Target creature with defender can attack this turn as though it didn't have defender.
{2}{G}: Creatures you control get +0/+1 until end of turn.

Swamp

Command Tower

{T}: Add one mana of any color in your commander's color identity.

Coat of Arms

Each creature gets +1/+1 for each other creature on the battlefield that shares at least one creature type with it. (For example, if two Goblin Warriors and a Goblin Shaman are on the battlefield, each gets +2/+2.)

Nyx Weaver

Reach
At the beginning of your upkeep, mill two cards. (Put the top two cards of your library into your graveyard.)
{1}{B}{G}, Exile this creature: Return target card from your graveyard to your hand.

Arasta of the Endless Web

Reach
Whenever an opponent casts an instant or sorcery spell, create a 1/2 green Spider creature token with reach.

Forest

Ancient Lumberknot

Each creature you control with toughness greater than its power assigns combat damage equal to its toughness rather than its power.

Deathreap Ritual

Morbid — At the beginning of each end step, if a creature died this turn, you may draw a card.

Grave Pact

Whenever a creature you control dies, each other player sacrifices a creature of their choice.

Academy Manufactor

If you would create a Clue, Food, or Treasure token, instead create one of each.

Kessig Recluse

Reach (This creature can block creatures with flying.)
Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)

Grim Tutor

Search your library for a card, put that card into your hand, then shuffle. You lose 3 life.

Hissing Miasma

Whenever a creature attacks you, its controller loses 1 life.

Beast Whisperer

Whenever you cast a creature spell, draw a card.

Twilight Mire

{T}: Add {C}.
{B/G}, {T}: Add {B}{B}, {B}{G}, or {G}{G}.

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Prey Upon

Target creature you control fights target creature you don't control. (Each deals damage equal to its power to the other.)

Night's Whisper

Deadly Recluse

Overgrown Tomb

({T}: Add {B} or {G}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.

Spider Food

Destroy up to one target artifact, enchantment, or creature with flying. Create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this token: You gain 3 life.")

Saryth, the Viper's Fang

Other tapped creatures you control have deathtouch.
Other untapped creatures you control have hexproof.
{1}, {T}: Untap another target creature or land you control.

Door of Destinies

As this artifact enters, choose a creature type.
Whenever you cast a spell of the chosen type, put a charge counter on this artifact.
Creatures you control of the chosen type get +1/+1 for each charge counter on this artifact.

Drider

Reach
Whenever this creature deals combat damage to a player, create a 2/1 black Spider creature token with menace and reach.

Penumbra Spider

Reach
When this creature dies, create a 2/4 black Spider creature token with reach.

Twin-Silk Spider

Reach
When this creature enters, create a 1/2 green Spider creature token with reach.

Llanowar Wastes

{T}: Add {C}.
{T}: Add {B} or {G}. This land deals 1 damage to you.

Ishkanah, Grafwidow

Reach
Delirium — When Ishkanah enters, if there are four or more card types among cards in your graveyard, create three 1/2 green Spider creature tokens with reach.
{6}{B}: Target opponent loses 1 life for each Spider you control.

Lolth, Spider Queen

Whenever a creature you control dies, put a loyalty counter on Lolth.
0: You draw a card and you lose 1 life.
−3: Create two 2/1 black Spider creature tokens with menace and reach.
−8: You get an emblem with "Whenever an opponent is dealt combat damage by one or more creatures you control, if that player lost less than 8 life this turn, they lose life equal to the difference."

Silklash Spider

Reach
{X}{G}{G}: This creature deals X damage to each creature with flying.

Brood Weaver

Reach
When this creature dies, create a 1/2 green Spider creature token with reach.

Mirkwood Bats

Flying
Whenever you create or sacrifice a token, each opponent loses 1 life.

Realmwalker

Changeling (This card is every creature type.)
As this creature enters, choose a creature type.
You may look at the top card of your library any time.
You may cast creature spells of the chosen type from the top of your library.

Curse of Clinging Webs

Enchant player
Whenever a nontoken creature enchanted player controls dies, exile it and you create a 1/2 green Spider creature token with reach.

Exotic Orchard

{T}: Add one mana of any color that a land an opponent controls could produce.

Giant Spider

Reach (This creature can block creatures with flying.)

Arcane Signet

Gloomwidow's Feast

Destroy target creature with flying. If that creature was blue or black, create a 1/2 green Spider creature token with reach. (It can block creatures with flying.)

Trail of Crumbs

When this enchantment enters, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this token: You gain 3 life.")
Whenever you sacrifice a Food, you may pay {1}. If you do, look at the top two cards of your library. You may reveal a permanent card from among them and put it into your hand. Put the rest on the bottom of your library in any order.

Sporeweb Weaver

Reach, hexproof from blue
Whenever this creature is dealt damage, you gain 1 life and create a 1/1 green Saproling creature token.

Rotwidow Pack

Reach
{3}{B}{G}, Exile a creature card from your graveyard: Create a 1/2 green Spider creature token with reach, then each opponent loses 1 life for each Spider you control.

Shelob, Child of Ungoliant

Deathtouch, ward {2}
Other Spiders you control have deathtouch and ward {2}.
Whenever another creature dealt damage this turn by a Spider you controlled dies, create a token that's a copy of that creature, except it's a Food artifact with "{2}, {T}, Sacrifice this token: You gain 3 life," and it loses all other card types.

Fyndhorn Elves

Treefolk Umbra

Enchant creature
Enchanted creature gets +0/+2 and assigns combat damage equal to its toughness rather than its power.
Umbra armor (If enchanted creature would be destroyed, instead remove all damage from it and destroy this Aura.)

Undergrowth Stadium

This land enters tapped unless you have two or more opponents.
{T}: Add {B} or {G}.

Sakura-Tribe Elder

Sacrifice this creature: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Putrefy

Destroy target artifact or creature. It can't be regenerated.

Necroblossom Snarl

As this land enters, you may reveal a Swamp or Forest card from your hand. If you don't, this land enters tapped.
{T}: Add {B} or {G}.

Spider Spawning

Create a 1/2 green Spider creature token with reach for each creature card in your graveyard.
Flashback {6}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Verdant Catacombs

{T}, Pay 1 life, Sacrifice this land: Search your library for a Swamp or Forest card, put it onto the battlefield, then shuffle.

Sol Ring

Skyfisher Spider

Reach
When this creature enters, you may sacrifice another creature. When you do, destroy target nonland permanent.
When this creature dies, you may gain 1 life for each creature card in your graveyard. If you do, exile this creature from your graveyard.

Crawlspace

No more than two creatures can attack you each combat.

Adaptive Automaton

As this creature enters, choose a creature type.
This creature is the chosen type in addition to its other types.
Other creatures you control of the chosen type get +1/+1.

Golgari Signet

Tainted Wood

{T}: Add {C}.
{T}: Add {B} or {G}. Activate only if you control a Swamp.

Rabid Bite

Target creature you control deals damage equal to its power to target creature you don't control.

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Shelob's Ambush

Target creature gets +1/+2 and gains deathtouch until end of turn. Create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this token: You gain 3 life.")

Vanquisher's Banner

As this artifact enters, choose a creature type.
Creatures you control of the chosen type get +1/+1.
Whenever you cast a creature spell of the chosen type, draw a card.

Doom Weaver

Reach
Soulbond (You may pair this creature with another unpaired creature when either enters. They remain paired for as long as you control both of them.)
As long as Doom Weaver is paired with another creature, each of those creatures has "When this creature dies, draw cards equal to its power."

Master's Rebuke

Target creature you control deals damage equal to its power to target creature or planeswalker you don't control.

Cosmic Hunger

Target creature you control deals damage equal to its power to another target creature, planeswalker, or battle.