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Winterthorn Blessing

Put a +1/+1 counter on up to one target creature you control. Tap up to one target creature you don't control, and that creature doesn't untap during its controller's next untap step.
Flashback {1}{G}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Forest

Froghemoth

Trample, haste
Whenever this creature deals combat damage to a player, exile up to that many target cards from their graveyard. Put a +1/+1 counter on this creature for each creature card exiled this way. You gain 1 life for each noncreature card exiled this way.

Island

Echo of Eons

Each player shuffles their hand and graveyard into their library, then draws seven cards.
Flashback {2}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Galloping Lizrog

Trample
When this creature enters, you may remove any number of +1/+1 counters from among creatures you control. If you do, put twice that many +1/+1 counters on this creature.

Rapid Hybridization

Destroy target creature. It can't be regenerated. That creature's controller creates a 3/3 green Frog Lizard creature token.

Plaxcaster Frogling

Graft 3 (This creature enters with three +1/+1 counters on it. Whenever another creature enters, you may move a +1/+1 counter from this creature onto it.)
{2}: Target creature with a +1/+1 counter on it gains shroud until end of turn. (It can't be the target of spells or abilities.)

Trollbred Guardian

{2}{G}: Adapt 2. (If this creature has no +1/+1 counters on it, put two +1/+1 counters on it.)
Each creature you control with a +1/+1 counter on it has trample.

Crocanura

Reach (This creature can block creatures with flying.)
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.)

Frogify

Enchant creature
Enchanted creature loses all abilities and is a blue Frog creature with base power and toughness 1/1. (It loses all other card types and creature types.)

Epiphany at the Drownyard

Reveal the top X plus one cards of your library and separate them into two piles. An opponent chooses one of those piles. Put that pile into your hand and the other into your graveyard.

Anurid Barkripper

Threshold — This creature gets +2/+2 as long as seven or more cards are in your graveyard.

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Sol Ring

Wild Growth

Enchant land
Whenever enchanted land is tapped for mana, its controller adds an additional {G}.

Shielding Plax

({G/U} can be paid with either {G} or {U}.)
Enchant creature
When this Aura enters, draw a card.
Enchanted creature can't be the target of spells or abilities your opponents control.

Chub Toad

Whenever this creature blocks or becomes blocked, it gets +2/+2 until end of turn.

Deranged Assistant

{T}, Mill a card: Add {C}. (To mill a card, put the top card of your library into your graveyard.)

Kasmina's Transmutation

Enchant creature
Enchanted creature loses all abilities and has base power and toughness 1/1.

Steeple Creeper

{3}{U}: This creature gains flying until end of turn.

Rhystic Study

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

Bower Passage

Creatures with flying can't block creatures you control.

Haze Frog

Flash (You may cast this spell any time you could cast an instant.)
When this creature enters, prevent all combat damage that other creatures would deal this turn.

Burrog Befuddler

Flash (You may cast this spell any time you could cast an instant.)
When this creature enters, target creature an opponent controls gets -1/-0 until end of turn.

Sword of the Animist

Equipped creature gets +1/+1.
Whenever equipped creature attacks, you may search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
Equip {2}

Timeless Witness

When this creature enters, return target card from your graveyard to your hand.
Eternalize {5}{G}{G} ({5}{G}{G}, Exile this card from your graveyard: Create a token that's a copy of it, except it's a 4/4 black Zombie Human Shaman with no mana cost. Eternalize only as a sorcery.)

Regrowth

Return target card from your graveyard to your hand.

Simic Charm

Choose one —
• Target creature gets +3/+3 until end of turn.
• Permanents you control gain hexproof until end of turn.
• Return target creature to its owner's hand.

Arcane Signet

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

Grolnok, the Omnivore

Whenever a Frog you control attacks, mill three cards.
Whenever a permanent card is put into your graveyard from your library, exile it with a croak counter on it.
You may play lands and cast spells from among cards you own in exile with croak counters on them.

Seal of Primordium

Sacrifice this enchantment: Destroy target artifact or enchantment.

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice this artifact: Draw a card.

Access Tunnel

{T}: Add {C}.
{3}, {T}: Target creature with power 3 or less can't be blocked this turn.

Biomass Mutation

Creatures you control have base power and toughness X/X until end of turn.

Command Tower

Bloated Toad

Protection from blue
Cycling {2} ({2}, Discard this card: Draw a card.)

Visions of Dominance

Put a +1/+1 counter on target creature, then double the number of +1/+1 counters on it.
Flashback {8}{G}{G}. This spell costs {X} less to cast this way, where X is the greatest mana value of a commander you own on the battlefield or in the command zone. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Font of Fertility

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

Satyr Wayfinder

When this creature 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.

Adaptive Automaton

As this creature enters, choose a creature type.
This creature is the chosen type in addition to its other types.
Other creatures you control of the chosen type get +1/+1.

Croaking Counterpart

Create a token that's a copy of target non-Frog creature, except it's a 1/1 green Frog.
Flashback {3}{G}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Leapfrog

This creature has flying as long as you've cast an instant or sorcery spell this turn.

Universal Automaton

Changeling (This card is every creature type.)

Anurid Swarmsnapper

Reach (This creature can block creatures with flying.)
{1}{G}: This creature can block an additional creature this turn.

Omnibian

{T}: Target creature becomes a Frog with base power and toughness 3/3 until end of turn.

Fertile Ground

Enchant land
Whenever enchanted land is tapped for mana, its controller adds an additional one mana of any color.

Omen of the Hunt

Flash
When this enchantment enters, you may search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
{2}{G}, Sacrifice this enchantment: Scry 2.

Eternal Witness

When this creature enters, you may return target card from your graveyard to your hand.

Expanded Anatomy

Put two +1/+1 counters on target creature. It gains vigilance until end of turn.

Winding Way

Choose creature or land. Reveal the top four cards of your library. Put all cards of the chosen type revealed this way into your hand and 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.)

Excavating Anurid

When this creature enters, you may sacrifice a land. If you do, draw a card.
Threshold — As long as seven or more cards are in your graveyard, this creature gets +1/+1 and has vigilance.

Polymorphist's Jest

Until end of turn, each creature target player controls loses all abilities and becomes a blue Frog with base power and toughness 1/1.

Alchemist's Refuge

{T}: Add {C}.
{G}{U}, {T}: You may cast spells this turn as though they had flash.

Beastmaster Ascension

Whenever a creature you control attacks, you may put a quest counter on this enchantment.
As long as this enchantment has seven or more quest counters on it, creatures you control get +5/+5.

Guardian Gladewalker

Changeling (This card is every creature type.)
When this creature enters, put a +1/+1 counter on target creature.

Aqueous Form

Enchant creature
Enchanted creature can't be blocked.
Whenever enchanted creature attacks, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Winged Boots

Equipped creature has flying and ward {4}. (Whenever equipped creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {4}.)
Equip {1}

Gravity Well

Whenever a creature with flying attacks, it loses flying until end of turn.

Primal Surge

Exile the top card of your library. If it's a permanent card, you may put it onto the battlefield. If you do, repeat this process.

Soul of New Phyrexia

Trample
{5}: Permanents you control gain indestructible until end of turn.
{5}, Exile this card from your graveyard: Permanents you control gain indestructible until end of turn.

Pedantic Learning

Whenever a land card is put into your graveyard from your library, you may pay {1}. If you do, draw a card.

Spore Frog

Sacrifice this creature: Prevent all combat damage that would be dealt this turn.

Day's Undoing

Each player shuffles their hand and graveyard into their library, then draws seven cards. If it's your turn, end the turn. (Exile all spells and abilities from the stack, including this card. Discard down to your maximum hand size. Damage wears off, and "this turn" and "until end of turn" effects end.)

Seal of Removal

Sacrifice this enchantment: Return target creature to its owner's hand.

Whiptongue Frog

{U}: This creature gains flying until end of turn.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Vineglimmer Snarl

As this land enters, you may reveal a Forest or Island card from your hand. If you don't, this land enters tapped.
{T}: Add {G} or {U}.

Millikin

Turn to Frog

Until end of turn, target creature loses all abilities and becomes a blue Frog with base power and toughness 1/1.

Mistwalker

Changeling (This card is every creature type.)
Flying
{1}{U}: This creature gets +1/-1 until end of turn.

Jade Avenger

Bushido 2 (Whenever this creature blocks or becomes blocked, it gets +2/+2 until end of turn.)

One with Nature

Enchant creature
Whenever enchanted creature deals combat damage to a player, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.