Urborg, Tomb of Yawgmoth

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

Drey Keeper

When Drey Keeper enters, create two 1/1 green Squirrel creature tokens.
{3}{B}: Squirrels you control get +1/+0 and gain menace until end of turn.

Squirrel Wrangler

{1}{G}, Sacrifice a land: Create two 1/1 green Squirrel creature tokens.
{1}{G}, Sacrifice a land: Squirrel creatures get +1/+1 until end of turn.

Chitterspitter

At the beginning of your upkeep, you may sacrifice a token. If you do, put an acorn counter on Chitterspitter.
Squirrels you control get +1/+1 for each acorn counter on Chitterspitter.
{G}, {T}: Create a 1/1 green Squirrel creature token.

Shamanic Revelation

Draw a card for each creature you control.
Ferocious — You gain 4 life for each creature you control with power 4 or greater.

Forest

Damnation

Destroy all creatures. They can't be regenerated.

Scurry Oak

Evolve (Whenever a creature you control enters, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.)
Whenever one or more +1/+1 counters are put on Scurry Oak, you may create a 1/1 green Squirrel creature token.

Ivy Lane Denizen

Whenever another green creature you control enters, put a +1/+1 counter on target creature.

Moldervine Reclamation

Whenever a creature you control dies, you gain 1 life and draw a card.

Rampant Growth

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

Pitiless Plunderer

Whenever another creature you control dies, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Wolverine Riders

At the beginning of each upkeep, create a 1/1 green Elf Warrior creature token.
Whenever another Elf you control enters, you gain life equal to its toughness.

Squirrel Sovereign

Avenger of Zendikar

When Avenger of Zendikar enters, create a 0/1 green Plant creature token for each land you control.
Landfall — Whenever a land you control enters, you may put a +1/+1 counter on each Plant creature you control.

Sol Ring

Saproling Symbiosis

You may cast Saproling Symbiosis as though it had flash if you pay {2} more to cast it. (You may cast it any time you could cast an instant.)
Create a 1/1 green Saproling creature token for each creature you control.

Species Specialist

As Species Specialist enters, choose a creature type.
Whenever a creature of the chosen type dies, you may draw a card.

Nested Shambler

When Nested Shambler dies, create X tapped 1/1 green Squirrel creature tokens, where X is Nested Shambler's power.

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.

Blunt the Assault

You gain 1 life for each creature on the battlefield. Prevent all combat damage that would be dealt this turn.

Ogre Slumlord

Whenever another nontoken creature dies, you may create a 1/1 black Rat creature token.
Rats you control have deathtouch.

Tendershoot Dryad

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
At the beginning of each upkeep, create a 1/1 green Saproling creature token.
Saprolings you control get +2/+2 as long as you have the city's blessing.

Deep Forest Hermit

Vanishing 3 (This creature enters with three time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
When Deep Forest Hermit enters, create four 1/1 green Squirrel creature tokens.
Squirrels you control get +1/+1.

Swamp

Blood Artist

Whenever Blood Artist or another creature dies, target player loses 1 life and you gain 1 life.

Village Rites

As an additional cost to cast this spell, sacrifice a creature.
Draw two cards.

Arbor Elf

Worldly Tutor

Search your library for a creature card, reveal it, then shuffle and put the card on top.

Persist

Return target nonlegendary creature card from your graveyard to the battlefield with a -1/-1 counter on it.

Craterhoof Behemoth

Haste
When Craterhoof Behemoth enters, creatures you control gain trample and get +X/+X until end of turn, where X is the number of creatures you control.

Eternal Witness

When Eternal Witness enters, you may return target card from your graveyard to your hand.

Verdant Force

At the beginning of each upkeep, create a 1/1 green Saproling creature token.

Poison-Tip Archer

Reach (This creature can block creatures with flying.)
Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Whenever another creature dies, each opponent loses 1 life.

Parallel Evolution

For each creature token on the battlefield, its controller creates a token that's a copy of that creature.
Flashback {4}{G}{G}{G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Krosan Grip

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Destroy target artifact or enchantment.

Cultivate

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Earthcraft

Tap an untapped creature you control: Untap target basic land.

Second Harvest

For each token you control, create a token that's a copy of that permanent.

Primal Vigor

If one or more tokens would be created, twice that many of those tokens are created instead.
If one or more +1/+1 counters would be put on a creature, twice that many +1/+1 counters are put on that creature instead.

Yavimaya, Cradle of Growth

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

Essence Warden

Whenever another creature enters, you gain 1 life.

Zulaport Cutthroat

Whenever Zulaport Cutthroat or another creature you control dies, each opponent loses 1 life and you gain 1 life.

Underworld Hermit

When Underworld Hermit enters, create a number of 1/1 green Squirrel creature tokens equal to your devotion to black. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)

Culling Ritual

Destroy each nonland permanent with mana value 2 or less. Add {B} or {G} for each permanent destroyed this way.

Phyrexian Tower

{T}: Add {C}.
{T}, Sacrifice a creature: Add {B}{B}.

Squirrel Nest

Enchant land
Enchanted land has "{T}: Create a 1/1 green Squirrel creature token."

Chatterfang, Squirrel General

Forestwalk (This creature can't be blocked as long as defending player controls a Forest.)
If one or more tokens would be created under your control, those tokens plus that many 1/1 green Squirrel creature tokens are created instead.
{B}, Sacrifice X Squirrels: Target creature gets +X/-X until end of turn.

Verdant Command

Choose two —
• Target player creates two tapped 1/1 green Squirrel creature tokens.
• Counter target loyalty ability of a planeswalker.
• Exile target card from a graveyard.
• Target player gains 3 life.

Druid's Call

Enchant creature
Whenever enchanted creature is dealt damage, its controller creates that many 1/1 green Squirrel creature tokens.

Swarmyard

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

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Demonic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Heroic Intervention

Permanents you control gain hexproof and indestructible until end of turn.

Parallel Lives

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.

Ashnod's Altar

Dictate of Erebos

Flash
Whenever a creature you control dies, each opponent sacrifices a creature.

Abrupt Decay

This spell can't be countered.
Destroy target nonland permanent with mana value 3 or less.

Arcane Signet

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

Squirrel Sanctuary

When Squirrel Sanctuary enters, create a 1/1 green Squirrel creature token.
Whenever a nontoken creature you control dies, you may pay {1}. If you do, return Squirrel Sanctuary to its owner's hand.

Herd Baloth

Whenever one or more +1/+1 counters are put on Herd Baloth, you may create a 4/4 green Beast creature token.

Putrefy

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

Chatter of the Squirrel

Create a 1/1 green Squirrel creature token.
Flashback {1}{G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Gruesome Fate

Each opponent loses 1 life for each creature you control.

Kodama's Reach

Twilight Mire

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

Squirrel Mob

Squirrel Mob gets +1/+1 for each other Squirrel on the battlefield.

Chatterstorm

Create a 1/1 green Squirrel creature token.
Storm (When you cast this spell, copy it for each spell cast before it this turn.)

Toski, Bearer of Secrets

This spell can't be countered.
Indestructible
Toski, Bearer of Secrets attacks each combat if able.
Whenever a creature you control deals combat damage to a player, draw a card.

Acorn Harvest

Create two 1/1 green Squirrel creature tokens.
Flashback—{1}{G}, Pay 3 life. (You may cast this card from your graveyard for its flashback cost. Then exile it.)