Rise of the Witch-king

Each player sacrifices a creature of their choice. If you sacrificed a creature this way, you may return another permanent card from your graveyard to the battlefield.

Halana, Kessig Ranger

Reach
Whenever another creature you control enters, you may pay {2}. When you do, that creature deals damage equal to its power to target creature.
Partner (You can have two commanders if both have partner.)

Silklash Spider

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

Overgrown Tomb

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

Swarmyard

{T}: Add {C}.
{T}: Regenerate target Insect, Rat, Spider, or Squirrel. (The next time it would be destroyed this turn, instead tap it, remove it from combat, and heal all damage on it.)

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.)

Sakura-Tribe Elder

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

Revenge of the Hunted

Until end of turn, target creature gets +6/+6 and gains trample, and all creatures able to block it this turn do so.
Miracle {G} (You may cast this card for its miracle cost when you draw it if it's the first card you drew this turn.)

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}.

Back for More

Return target creature card from your graveyard to the battlefield. When you do, it fights up to one target creature you don't control. (Each deals damage equal to its power to the other.)

Swift Spinner

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

Ancient Lumberknot

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

Bushwhack

Choose one —
• Search your library for a basic land card, reveal it, put it into your hand, then shuffle.
• Target creature you control fights target creature you don't control. (Each deals damage equal to its power to the other.)

Phyrexian Arena

At the beginning of your upkeep, you draw a card and you lose 1 life.

Cosmic Hunger

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

Stinging Study

You draw X cards and you lose X life, where X is the mana value of a commander you own on the battlefield or in the command zone.

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."

Graveshifter

Changeling (This card is every creature type.)
When this creature enters, you may return target creature card from your graveyard to your hand.

Lure

Enchant creature
All creatures able to block enchanted creature do so.

Brood Weaver

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

Last March of the Ents

This spell can't be countered.
Draw cards equal to the greatest toughness among creatures you control, then put any number of creature cards from your hand onto the battlefield.

Snarespinner

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

Twin-Silk Spider

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

Entish Restoration

Sacrifice a land. Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle. If you control a creature with power 4 or greater, instead search your library for up to three basic land cards, put them onto the battlefield tapped, then shuffle.

Glowstone Recluse

Mutate {3}{G} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)
Reach
Whenever this creature mutates, put two +1/+1 counters on it.

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.

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.

Pounce

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

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.

Setessan Tactics

Strive — This spell costs {G} more to cast for each target beyond the first.
Until end of turn, any number of target creatures each get +1/+1 and gain "{T}: This creature fights another target creature."

Penumbra Spider

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

Cabal Coffers

{2}, {T}: Add {B} for each Swamp you control.

Castle Locthwain

This land enters tapped unless you control a Swamp.
{T}: Add {B}.
{1}{B}{B}, {T}: Draw a card, then you lose life equal to the number of cards in your hand.

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.

Nemesis Mask

All creatures able to block equipped creature do so.
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery. This card enters unattached and stays on the battlefield if the creature leaves.)

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.

Watcher in the Web

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

Deadly Dispute

As an additional cost to cast this spell, sacrifice an artifact or creature.
Draw two cards and create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Jaheira, Friend of the Forest

Tokens you control have "{T}: Add {G}."
Choose a Background (You can have a Background as a second commander.)

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.

Juvenile Gloomwidow

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

Bite Down

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

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.

Drider

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

Gyome, Master Chef

Trample
At the beginning of your end step, create a number of Food tokens equal to the number of nontoken creatures you had enter under your control this turn.
{1}, Sacrifice a Food: Target creature gains indestructible until end of turn. Tap it.

Chainweb Aracnir

Reach
When this creature enters, it deals damage equal to its power to target creature with flying an opponent controls.
Escape—{3}{G}{G}, Exile four other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.)
This creature escapes with three +1/+1 counters on it.

Urborg, Tomb of Yawgmoth

Each land is a Swamp in addition to its other land types.

Canopy Spider

Reach (This creature can block creatures with flying.)

Master's Rebuke

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.

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.

Masked Vandal

Changeling (This card is every creature type.)
When this creature enters, you may exile a creature card from your graveyard. If you do, exile target artifact or enchantment an opponent controls.

Castle Garenbrig

This land enters tapped unless you control a Forest.
{T}: Add {G}.
{2}{G}{G}, {T}: Add six {G}. Spend this mana only to cast creature spells or activate abilities of creatures.