Spiked Ripsaw

Equipped creature gets +3/+3.
Whenever equipped creature attacks, you may sacrifice a Forest. If you do, that creature gains trample until end of turn.
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)

Lost in the Woods

Whenever a creature attacks you or a planeswalker you control, reveal the top card of your library. If it's a Forest card, remove that creature from combat. Then put the revealed card on the bottom of your library.

Old-Growth Troll

Trample
When Old-Growth Troll dies, if it was a creature, return it to the battlefield. It's an Aura enchantment with enchant Forest you control and "Enchanted Forest has '{T}: Add {G}{G}' and '{1}, {T}, Sacrifice this land: Create a tapped 4/4 green Troll Warrior creature token with trample.'"

Arbor Elf

Nissa's Triumph

Search your library for up to two basic Forest cards. If you control a Nissa planeswalker, instead search your library for up to three land cards. Reveal those cards, put them into your hand, then shuffle.

Gaea's Touch

{0}: You may put a basic Forest card from your hand onto the battlefield. Activate only as a sorcery and only once each turn.
Sacrifice Gaea's Touch: Add {G}{G}.

Skyshroud Claim

Search your library for up to two Forest cards, put them onto the battlefield, then shuffle.

Demolition Field

{T}: Add {C}.
{2}, {T}, Sacrifice Demolition Field: Destroy target nonbasic land an opponent controls. That land's controller may search their library for a basic land card, put it onto the battlefield, then shuffle. You may search your library for a basic land card, put it onto the battlefield, then shuffle.

Song of the Dryads

Enchant permanent
Enchanted permanent is a colorless Forest land.

Treefolk Seedlings

Treefolk Seedlings's toughness is equal to the number of Forests you control.

Tangle Golem

Affinity for Forests (This spell costs {1} less to cast for each Forest you control.)

Land Grant

If you have no land cards in hand, you may reveal your hand rather than pay this spell's mana cost.
Search your library for a Forest card, reveal that card, put it into your hand, then shuffle.

Nissa, Who Shakes the World

Whenever you tap a Forest for mana, add an additional {G}.
+1: Put three +1/+1 counters on up to one target noncreature land you control. Untap it. It becomes a 0/0 Elemental creature with vigilance and haste that's still a land.
−8: You get an emblem with "Lands you control have indestructible." Search your library for any number of Forest cards, put them onto the battlefield tapped, then shuffle.

Yavimaya Dryad

Forestwalk (This creature can't be blocked as long as defending player controls a Forest.)
When Yavimaya Dryad enters the battlefield, you may search your library for a Forest card, put it onto the battlefield tapped under target player's control, then shuffle.

Llanowar Druid

{T}, Sacrifice Llanowar Druid: Untap all Forests.

Staff of Titania

Equipped creature gets +X/+X, where X is the number of Forests you control.
Whenever equipped creature attacks, create a 1/1 green Forest Dryad land creature token. (It's affected by summoning sickness.)
Equip {3}

Reach of Branches

Create a 2/5 green Treefolk Shaman creature token.
Whenever a Forest enters the battlefield under your control, you may return Reach of Branches from your graveyard to your hand.

Patron of the Orochi

Snake offering (You may cast this card any time you could cast an instant by sacrificing a Snake and paying the difference in mana costs between this and the sacrificed Snake. Mana cost includes color.)
{T}: Untap all Forests and all green creatures. Activate only once each turn.

Beacon of Creation

Create a 1/1 green Insect creature token for each Forest you control. Shuffle Beacon of Creation into its owner's library.

Ranger's Path

Search your library for up to two Forest cards, put them onto the battlefield tapped, then shuffle.

Neverwinter Dryad

{2}, Sacrifice Neverwinter Dryad: Search your library for a basic Forest card, put it onto the battlefield tapped, then shuffle.

Scryb Ranger

Flash
Flying, protection from blue
Return a Forest you control to its owner's hand: Untap target creature. Activate only once each turn.

Invigorate

If you control a Forest, rather than pay this spell's mana cost, you may have an opponent gain 3 life.
Target creature gets +4/+4 until end of turn.

Primal Bellow

Target creature gets +1/+1 until end of turn for each Forest you control.

Wasteland

{T}: Add {C}.
{T}, Sacrifice Wasteland: Destroy target nonbasic land.

Crash Landing

Target creature with flying loses flying until end of turn. Crash Landing deals damage to that creature equal to the number of Forests you control.

People of the Woods

People of the Woods's toughness is equal to the number of Forests you control.

Waiting in the Weeds

Each player creates a 1/1 green Cat creature token for each untapped Forest they control.

Fruition

You gain 1 life for each Forest on the battlefield.

Gaea's Bounty

Search your library for up to two Forest cards, reveal those cards, put them into your hand, then shuffle.

Howl of the Night Pack

Create a 2/2 green Wolf creature token for each Forest you control.

Refreshing Rain

If an opponent controls a Swamp and you control a Forest, you may cast this spell without paying its mana cost.
Target player gains 6 life.

Nature's Lore

Search your library for a Forest card, put that card onto the battlefield, then shuffle.

Nissa's Encouragement

Search your library and graveyard for a card named Forest, a card named Brambleweft Behemoth, and a card named Nissa, Genesis Mage. Reveal those cards, put them into your hand, then shuffle.

Spectrum Sentinel

Protection from multicolored (This creature can't be blocked, targeted, dealt damage, enchanted, or equipped by anything multicolored.)
Whenever a nonbasic land enters the battlefield under an opponent's control, you gain 1 life.

Myriad Construct

Kicker {3}
If Myriad Construct was kicked, it enters the battlefield with a +1/+1 counter on it for each nonbasic land your opponents control.
When Myriad Construct becomes the target of a spell, sacrifice it and create a number of 1/1 colorless Construct artifact creature tokens equal to its power.

Woodland Guidance

Return target card from your graveyard to your hand. Clash with an opponent. If you win, untap all Forests you control. (Each clashing player reveals the top card of their library, then puts that card on the top or bottom. A player wins if their card had a higher mana value.)
Exile Woodland Guidance.

Vernal Bloom

Whenever a Forest is tapped for mana, its controller adds an additional {G}.

Dungrove Elder

Hexproof (This creature can't be the target of spells or abilities your opponents control.)
Dungrove Elder's power and toughness are each equal to the number of Forests you control.

Hunting Cheetah

Whenever Hunting Cheetah deals damage to an opponent, you may search your library for a Forest card, reveal that card, put it into your hand, then shuffle.

Battlewand Oak

Whenever a Forest enters the battlefield under your control, Battlewand Oak gets +2/+2 until end of turn.
Whenever you cast a Treefolk spell, Battlewand Oak gets +2/+2 until end of turn.

Sylvan Primordial

Reach
When Sylvan Primordial enters the battlefield, for each opponent, destroy target noncreature permanent that player controls. For each permanent destroyed this way, search your library for a Forest card and put that card onto the battlefield tapped. Then shuffle.

Traproot Kami

Defender; reach (This creature can block creatures with flying.)
Traproot Kami's toughness is equal to the number of Forests on the battlefield.

Titania, Nature's Force

You may play Forests from your graveyard.
Whenever a Forest enters the battlefield under your control, create a 5/3 green Elemental creature token.
Whenever an Elemental you control dies, you may mill three cards.

Wave of Vitriol

Each player sacrifices all artifacts, enchantments, and nonbasic lands they control. For each land sacrificed this way, its controller may search their library for a basic land card and put it onto the battlefield tapped. Then each player who searched their library this way shuffles.

Seedguide Ash

When Seedguide Ash dies, you may search your library for up to three Forest cards, put them onto the battlefield tapped, then shuffle.

Tectonic Edge

{T}: Add {C}.
{1}, {T}, Sacrifice Tectonic Edge: Destroy target nonbasic land. Activate only if an opponent controls four or more lands.

Blanchwood Armor

Enchant creature
Enchanted creature gets +1/+1 for each Forest you control.

Mwonvuli Acid-Moss

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

Harold and Bob, First Numens

Vigilance, reach
When Harold and Bob, First Numens dies, if it was a creature, return it to the battlefield. It's an Aura enchantment with enchant Forest you control and "Enchanted Forest has '{T}: Add three mana of any one color. You get two rad counters.'" Harold and Bob loses all other abilities.

Primal Order

At the beginning of each player's upkeep, Primal Order deals damage to that player equal to the number of nonbasic lands they control.

Quirion Ranger

Return a Forest you control to its owner's hand: Untap target creature. Activate only once each turn.

Volatile Fault

{T}: Add {C}.
{1}, {T}, Sacrifice Volatile Fault: Destroy target nonbasic land an opponent controls. That player may search their library for a basic land card, put it onto the battlefield, then shuffle. You create a Treasure token.

Baru, Fist of Krosa

Whenever a Forest enters the battlefield, green creatures you control get +1/+1 and gain trample until end of turn.
Grandeur — Discard another card named Baru, Fist of Krosa: Create an X/X green Wurm creature token, where X is the number of lands you control.

Keeper of Progenitus

Whenever a player taps a Mountain, Forest, or Plains for mana, that player adds one mana of any type that land produced.

Kalonian Twingrove

Kalonian Twingrove's power and toughness are each equal to the number of Forests you control.
When Kalonian Twingrove enters the battlefield, create a green Treefolk Warrior creature token with "This creature's power and toughness are each equal to the number of Forests you control."

Generous Ent

Reach
When Generous Ent enters the battlefield, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life.")
Forestcycling {1} ({1}, Discard this card: Search your library for a Forest card, reveal it, put it into your hand, then shuffle.)

Nissa's Pilgrimage

Search your library for up to two basic Forest cards, reveal those cards, and put one onto the battlefield tapped and the rest into your hand. Then shuffle.
Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, search your library for up to three basic Forest cards instead of two.

Three Visits

Search your library for a Forest card, put it onto the battlefield, then shuffle.

Brawn

Trample
As long as Brawn is in your graveyard and you control a Forest, creatures you control have trample.

Winter Moon

Players can't untap more than one nonbasic land during their untap steps.

Trailblazer's Boots

Equipped creature has nonbasic landwalk. (It can't be blocked as long as defending player controls a nonbasic land.)
Equip {2}

Coiling Woodworm

Coiling Woodworm's power is equal to the number of Forests on the battlefield.

Genju of the Cedars

Enchant Forest
{2}: Enchanted Forest becomes a 4/4 green Spirit creature until end of turn. It's still a land.
When enchanted Forest is put into a graveyard, you may return Genju of the Cedars from your graveyard to your hand.

Nessian Game Warden

When Nessian Game Warden enters the battlefield, look at the top X cards of your library, where X is the number of Forests you control. You may reveal a creature card from among them and put it into your hand. Put the rest on the bottom of your library in any order.

Hunting Wilds

Kicker {3}{G} (You may pay an additional {3}{G} as you cast this spell.)
Search your library for up to two Forest cards, put them onto the battlefield tapped, then shuffle.
If this spell was kicked, untap all Forests put onto the battlefield this way. They become 3/3 green creatures with haste that are still lands.

Nissa, Sage Animist

+1: Reveal the top card of your library. If it's a land card, put it onto the battlefield. Otherwise, put it into your hand.
−2: Create Ashaya, the Awoken World, a legendary 4/4 green Elemental creature token.
−7: Untap up to six target lands. They become 6/6 Elemental creatures. They're still lands.

Nissa, Vastwood Seer

When Nissa, Vastwood Seer enters the battlefield, you may search your library for a basic Forest card, reveal it, put it into your hand, then shuffle.
Whenever a land enters the battlefield under your control, if you control seven or more lands, exile Nissa, then return her to the battlefield transformed under her owner's control.

Nissa, Vastwood Seer // Nissa, Sage Animist

Utopia Sprawl

Enchant Forest
As Utopia Sprawl enters the battlefield, choose a color.
Whenever enchanted Forest is tapped for mana, its controller adds an additional one mana of the chosen color.

Aspect of Wolf

Enchant creature
Enchanted creature gets +X/+Y, where X is half the number of Forests you control, rounded down, and Y is half the number of Forests you control, rounded up.