Might Beyond Reason

Put two +1/+1 counters on target creature.
Delirium — Put three +1/+1 counters on that creature instead if there are four or more card types among cards in your graveyard.

Keening Stone

{5}, {T}: Target player mills X cards, where X is the number of cards in that player's graveyard.

Umbral Collar Zealot

Sacrifice another creature or artifact: Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Dim Oubliette

When you unlock this door, mill three cards, then return a creature card from your graveyard to the battlefield.
(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)

Polluted Cistern

Whenever one or more cards are put into your graveyard from your library, each opponent loses 1 life for each card type among those cards.
(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)

Polluted Cistern // Dim Oubliette

Drudge Beetle

Scavenge {5}{G} ({5}{G}, Exile this card from your graveyard: Put a number of +1/+1 counters equal to this card's power on target creature. Scavenge only as a sorcery.)

Swamp

Ironshell Beetle

When this creature enters, put a +1/+1 counter on target creature.

Requiem Monolith

{T}: Until end of turn, target creature gains "Whenever this creature is dealt damage, you draw that many cards and lose that much life." That creature's controller may have this artifact deal 1 damage to it. Activate only as a sorcery.

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}.

Wall Crawl

When this enchantment enters, create a 2/1 green Spider creature token with reach, then you gain 1 life for each Spider you control.
Spiders you control get +1/+1 and can't be blocked by creatures with defender.

Duskshell Crawler

When this creature enters, put a +1/+1 counter on target creature.
Each creature you control with a +1/+1 counter on it has trample. (It can deal excess combat damage to the player or planeswalker it's attacking.)

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.)

Retrofitted Transmogrant

{3}{B}: Return this card from your graveyard to the battlefield tapped with two +1/+1 counters on it.

Vorapede

Vigilance, trample
Undying (When this creature dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

Cemetery Tampering

Hideaway 5 (When this enchantment enters, look at the top five cards of your library, exile one face down, then put the rest on the bottom in a random order.)
At the beginning of your upkeep, you may mill three cards. Then if there are twenty or more cards in your graveyard, you may play the exiled card without paying its mana cost.

Blister Beetle

When this creature enters, target creature gets -1/-1 until end of turn.

Pincer Spider

Kicker {3} (You may pay an additional {3} as you cast this spell.)
Reach (This creature can block creatures with flying.)
If this creature was kicked, it enters with a +1/+1 counter on it.

Skystinger

Reach
Whenever this creature blocks a creature with flying, this creature gets +5/+0 until end of turn.

Swift Spinner

Flash (You may cast this spell any time you could cast an instant.)
Reach (This creature can block creatures with flying.)

Spider-Man, Brooklyn Visionary

Web-slinging {2}{G} (You may cast this spell for {2}{G} if you also return a tapped creature you control to its owner's hand.)
When Spider-Man enters, search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Molt Tender

{T}: Mill a card. (Put the top card of your library into your graveyard.)
{T}, Exile a card from your graveyard: Add one mana of any color.

Moldgraf Millipede

When this creature enters, mill three cards, then put a +1/+1 counter on this creature for each creature card in your graveyard. (To mill three cards, put the top three cards of your library into your graveyard.)

Mindless Automaton

This creature enters with two +1/+1 counters on it.
{1}, Discard a card: Put a +1/+1 counter on this creature.
Remove two +1/+1 counters from this creature: Draw a card.

Kraul Harpooner

Reach
Undergrowth — When this creature enters, choose up to one target creature you don't control with flying. This creature gets +X/+0 until end of turn, where X is the number of creature cards in your graveyard, then you may have this creature fight that creature.

Deadbridge Chant

When this enchantment enters, mill ten cards.
At the beginning of your upkeep, choose a card at random in your graveyard. If it's a creature card, put it onto the battlefield. Otherwise, put it into your hand.

Giant Dustwasp

Flying
Suspend 4—{1}{G} (Rather than cast this card from your hand, you may pay {1}{G} and exile it with four time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost. It has haste.)

Dryad Arbor

(This land isn't a spell, it's affected by summoning sickness, and it has "{T}: Add {G}.")

Diamond Weapon

This spell costs {1} less to cast for each permanent card in your graveyard.
Reach
Immune — Prevent all combat damage that would be dealt to Diamond Weapon.

Golgari Locket

{T}: Add {B} or {G}.
{B/G}{B/G}{B/G}{B/G}, {T}, Sacrifice this artifact: Draw two cards.

Temple of Malady

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {B} or {G}.

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.

Vault of Whispers

Ursine Monstrosity

Trample
At the beginning of combat on your turn, mill a card and choose an opponent at random. This creature attacks that player this combat if able. Until end of turn, this creature gains indestructible and gets +1/+1 for each card type among cards in your graveyard.

Grave Strength

Choose target creature. Mill three cards, then put a +1/+1 counter on that creature for each creature card in your graveyard. (To mill three cards, put the top three cards of your library into your graveyard.)

Grisly Salvage

Reveal the top five cards of your library. You may put a creature or land card from among them into your hand. Put the rest into your graveyard.

Grapple with the Past

Mill three cards, then you may return a creature or land card from your graveyard to your hand. (To mill three cards, put the top three cards of your library into your graveyard.)

Mineshaft Spider

Reach
When this creature enters, you may mill two cards. (You may put the top two cards of your library into your graveyard.)

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.

Commune with the Gods

Reveal the top five cards of your library. You may put a creature or enchantment card from among them into your hand. Put the rest into your graveyard.

Forest

Hitchclaw Recluse

Ezekiel Sims, Spider-Totem

Reach
At the beginning of combat on your turn, target Spider you control gets +2/+2 until end of turn.

Penumbra Spider

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

Undergrowth Stadium

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

Skylasher

Flash
This spell can't be countered.
Reach, protection from blue

Giant Spider

Reach (This creature can block creatures with flying.)

Witch's Cauldron

{1}{B}, {T}, Sacrifice a creature: You gain 1 life and draw a card.

Broodspinner

Reach
When this creature enters, surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)
{4}{B}{G}, {T}, Sacrifice this creature: Create a number of 1/1 black and green Insect creature tokens with flying equal to the number of card types among cards in your graveyard.

Atrocious Experiment

Target player mills two cards, draws two cards, and loses 2 life. (To mill a card, a player puts the top card of their library into their graveyard.)

Silklash Spider

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

Skola Grovedancer

Whenever a land card is put into your graveyard from anywhere, you gain 1 life.
{2}{G}: Mill a card. (Put the top card of your library into your graveyard.)

Hateful Eidolon

Lifelink
Whenever an enchanted creature dies, draw a card for each Aura you controlled that was attached to it.

Command Tower

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

Spinner of Souls

Reach
Whenever another nontoken creature you control dies, you may reveal cards from the top of your library until you reveal a creature card. Put that card into your hand and the rest on the bottom of your library in a random order.

Eccentric Farmer

When this creature enters, mill three cards, then you may return a land card from your graveyard to your hand. (To mill three cards, put the top three cards of your library into your graveyard.)

Funnel-Web Recluse

Reach
Morbid — When this creature enters, if a creature died this turn, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")

Excavated Wall

Defender
{1}, {T}: Mill a card. (Put the top card of your library into your graveyard.)

Benefaction of Rhonas

Reveal the top five cards of your library. You may put a creature card and/or an enchantment card from among them into your hand. Put the rest into your graveyard.

Sparring Construct

When this creature dies, put a +1/+1 counter on target creature you control.

Skittering Heartstopper

{B}: This creature gains deathtouch until end of turn.

Hidden Grotto

When this land enters, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Tree of Tales

Corpse Churn

Mill three cards, then you may return a creature card from your graveyard to your hand. (To mill three cards, put the top three cards of your library into your graveyard.)

It of the Horrid Swarm

Emerge {6}{G} (You may cast this spell by sacrificing a creature and paying the emerge cost reduced by that creature's mana value.)
When you cast this spell, create two 1/1 green Insect creature tokens.

Brood of Cockroaches

When this creature is put into your graveyard from the battlefield, at the beginning of the next end step, you lose 1 life and return this card to your hand.

Relentless Pursuit

Reveal the top four cards of your library. You may put a creature card and/or a land card from among them into your hand. Put the rest into your graveyard.

Inscribed Tablet

{1}, {T}, Sacrifice this artifact: Reveal the top five cards of your library. Put a land card from among them into your hand and the rest on the bottom of your library in a random order. If you didn't put a card into your hand this way, draw a card.

Carrion Grub

This creature gets +X/+0, where X is the greatest power among creature cards in your graveyard.
When this creature enters, mill four cards. (Put the top four cards of your library into your graveyard.)

Sol Ring

Crawling Sensation

At the beginning of your upkeep, you may mill two cards. (You may put the top two cards of your library into your graveyard.)
Whenever one or more land cards are put into your graveyard from anywhere for the first time each turn, create a 1/1 green Insect creature token.

Vessel of Nascency

{1}{G}, Sacrifice this enchantment: Reveal the top four cards of your library. You may put an artifact, creature, enchantment, land, or planeswalker card from among them into your hand. Put the rest into your graveyard.

Llanowar Wastes

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

Hornet Queen

Flying, deathtouch
When this creature enters, create four 1/1 green Insect creature tokens with flying and deathtouch.

Spineseeker Centipede

When this creature enters, search your library for a basic land card, reveal it, put it into your hand, then shuffle.
Delirium — This creature gets +1/+2 and has vigilance as long as there are four or more card types among cards in your graveyard.

Kraul Foragers

Undergrowth — When this creature enters, you gain 1 life for each creature card in your graveyard.

Skysnare Spider

Vigilance (Attacking doesn't cause this creature to tap.)
Reach (This creature can block creatures with flying.)

The Hunger Tide Rises

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after IV.)
I, II, III — Create a 1/1 black and green Insect creature token.
IV — Sacrifice any number of creatures. Search your library and/or graveyard for a creature card with mana value less than or equal to the number of creatures sacrificed this way and put it onto the battlefield. If you search your library this way, shuffle.

Jermane, Pride of the Circus

{G}, {T}: Put two +1/+1 counters on target creature with four or more legs.
{1}{G}{G}, {T}: Until end of turn, all creatures able to block target creature with four or more legs do so.

Obelisk Spider

Reach
Whenever this creature deals combat damage to a creature, put a -1/-1 counter on that creature.
Whenever you put one or more -1/-1 counters on a creature, each opponent loses 1 life and you gain 1 life.

Darkmoss Bridge

This land enters tapped.
Indestructible
{T}: Add {B} or {G}.

Treetop Snarespinner

Reach (This creature can block creatures with flying.)
Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
{2}{G}: Put a +1/+1 counter on target creature you control. Activate only as a sorcery.

Huskburster Swarm

This spell costs {1} less to cast for each creature card you own in exile and in your graveyard.
Menace, deathtouch

Graveyard Shift

This spell has flash as long as there are five or more mana values among cards in your graveyard.
Return target creature card from your graveyard to the battlefield.

Netcaster Spider

Reach (This creature can block creatures with flying.)
Whenever this creature blocks a creature with flying, this creature gets +2/+0 until end of turn.

Seedship Broodtender

When this creature enters, mill three cards. (Put the top three cards of your library into your graveyard.)
{3}{B}{G}, Sacrifice this creature: Return target creature or Spacecraft card from your graveyard to the battlefield. Activate only as a sorcery.

Insidious Roots

Creature tokens you control have "{T}: Add one mana of any color."
Whenever one or more creature cards leave your graveyard, create a 0/1 green Plant creature token, then put a +1/+1 counter on each Plant you control.

Millstone

Macabre Waltz

Return up to two target creature cards from your graveyard to your hand, then discard a card.

The Mending of Dominaria

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Mill two cards, then you may return a creature card from your graveyard to your hand.
III — Return all land cards from your graveyard to the battlefield, then shuffle your graveyard into your library.

The Swarmweaver

When The Swarmweaver enters, create two 1/1 black and green Insect creature tokens with flying.
Delirium — As long as there are four or more card types among cards in your graveyard, Insects and Spiders you control get +1/+1 and have deathtouch.

Canopy Spider

Giant Adephage

Trample
Whenever this creature deals combat damage to a player, create a token that's a copy of this creature.

Nessian Hornbeetle

At the beginning of combat on your turn, if you control another creature with power 4 or greater, put a +1/+1 counter on this creature.

Quarry Beetle

When this creature enters, you may return target land card from your graveyard to the battlefield.

Crash of Rhino Beetles

Trample
This creature gets +10/+10 as long as you control ten or more lands.

Deal Gone Bad

Target creature gets -3/-3 until end of turn. Target player mills three cards. (They put the top three cards of their library into their graveyard.)

Mammoth Spider

Sporecap Spider

Hornet Nest

Defender (This creature can't attack.)
Whenever this creature is dealt damage, create that many 1/1 green Insect creature tokens with flying and deathtouch. (Any amount of damage a creature with deathtouch deals to a creature is enough to destroy it.)

Virus Beetle

When this creature enters, each opponent discards a card.

Icetill Explorer

You may play an additional land on each of your turns.
You may play lands from your graveyard.
Landfall — Whenever a land you control enters, mill a card.

Valgavoth's Onslaught

Manifest dread X times, then put X +1/+1 counters on each of those creatures. (To manifest dread, look at the top two cards of your library, then put one onto the battlefield face down as a 2/2 creature and the other into your graveyard. Turn it face up any time for its mana cost if it's a creature card.)

Rot Farm Mortipede

Whenever one or more creature cards leave your graveyard, this creature gets +1/+0 and gains menace and lifelink until end of turn.

Grow Extra Arms

This spell costs {1} less to cast if it targets a Spider.
Target creature gets +4/+4 until end of turn.