Ransack the Lab

Look at the top three cards of your library. Put one of them into your hand and the rest into your graveyard.

Twin-Silk Spider

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

Canopy Spider

Reach (This creature can block creatures with flying.)

Plated Spider

Tangle Spider

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

Somberwald Spider

Reach (This creature can block creatures with flying.)
Morbid — Somberwald Spider enters with two +1/+1 counters on it if a creature died this turn.

Frostweb Spider

Reach (This creature can block creatures with flying.)
Whenever Frostweb Spider blocks a creature with flying, put a +1/+1 counter on Frostweb Spider at end of combat.

Hitchclaw Recluse

Juvenile Gloomwidow

Reach (This creature can block creatures with flying.)
Wither (This deals damage to creatures in the form of -1/-1 counters.)

Giant Spider

Satyr Wayfinder

When Satyr Wayfinder enters, reveal the top four cards of your library. You may put a land card from among them into your hand. Put the rest into your graveyard.

Vessel of Nascency

{1}{G}, Sacrifice Vessel of Nascency: 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.

Deadly Recluse

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

Urborg Syphon-Mage

{2}{B}, {T}, Discard a card: Each other player loses 2 life. You gain life equal to the life lost this way.

Yavimaya Elder

When Yavimaya Elder dies, you may search your library for up to two basic land cards, reveal them, put them into your hand, then shuffle.
{2}, Sacrifice Yavimaya Elder: Draw a card.

Swift Spinner

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.

Watcher in the Web

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

Woolly Spider

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

Kessig Recluse

Snarespinner

Reach
Whenever Snarespinner blocks a creature with flying, Snarespinner gets +2/+0 until end of turn.

Aquastrand Spider

Graft 2 (This creature enters with two +1/+1 counters on it. Whenever another creature enters, you may move a +1/+1 counter from this creature onto it.)
{G}: Target creature with a +1/+1 counter on it gains reach until end of turn. (It can block creatures with flying.)

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.)

Blightwidow

Reach (This creature can block creatures with flying.)
Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Penumbra Spider

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

Renowned Weaver

{1}{G}, Sacrifice Renowned Weaver: Create a 1/3 green Spider enchantment creature token with reach. (It can block creatures with flying.)

Venomous Changeling

Changeling (This card is every creature type.)
Deathtouch

Rib Cage Spider

Changeling Outcast

Changeling (This card is every creature type.)
Changeling Outcast can't block and can't be blocked.

Game-Trail Changeling

Changeling (This card is every creature type.)
Trample

Bitter Revelation

Look at the top four cards of your library. Put two of them into your hand and the rest into your graveyard. You lose 2 life.

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.

Sporecap Spider

Skirsdag Supplicant

{B}, {T}, Discard a card: Each player loses 2 life.

Jungle Weaver

Reach (This creature can block creatures with flying.)
Cycling {2} ({2}, Discard this card: Draw a card.)

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.

Dark Bargain

Look at the top three cards of your library. Put two of them into your hand and the other into your graveyard. Dark Bargain deals 2 damage to you.

Sakura-Tribe Elder

Sacrifice Sakura-Tribe Elder: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Hidden Spider

When an opponent casts a creature spell with flying, if Hidden Spider is an enchantment, Hidden Spider becomes a 3/5 Spider creature with reach. (It can block creatures with flying.)

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.)

Krosan Tusker

Cycling {2}{G} ({2}{G}, Discard this card: Draw a card.)
When you cycle Krosan Tusker, you may search your library for a basic land card, reveal that card, put it into your hand, then shuffle. (Do this before you draw.)

Dawntreader Elk

{G}, Sacrifice Dawntreader Elk: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Shambling Shell

Sacrifice Shambling Shell: 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.)

Caustic Caterpillar

{1}{G}, Sacrifice Caustic Caterpillar: Destroy target artifact or enchantment.

Netcaster Spider

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