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.)

Unwilling Ingredient

Menace (This creature can't be blocked except by two or more creatures.)
{2}{B}, Exile Unwilling Ingredient from your graveyard: You draw a card and you lose 1 life.

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.)

Entropic Decay

Mill four cards. (Then exile this card. You may cast the creature later from exile.)

Gray Slaad

As long as there are four or more creature cards in your graveyard, Gray Slaad has menace and deathtouch.

Gray Slaad // Entropic Decay

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.

Feast of Succession

All creatures get -4/-4 until end of turn. You become the monarch.

Kaya's Ghostform

Enchant creature or planeswalker you control
When enchanted permanent dies or is put into exile, return that card to the battlefield under your control.

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.)

Jade Avenger

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

Wretched Anurid

Whenever another creature enters, you lose 1 life.

Audacity

Enchant creature
Enchanted creature gets +2/+0 and has trample. (It can deal excess combat damage to the player or planeswalker it's attacking.)
When Audacity is put into a graveyard from the battlefield, draw a card.

Steeple Creeper

{3}{U}: Steeple Creeper gains flying until end of turn.

Kasmina's Transmutation

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

Chub Toad

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

Yargle, Glutton of Urborg

Haze Frog

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

Froghemoth

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

Anurid Swarmsnapper

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

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.

Turn to Frog

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

Whiptongue Frog

{U}: Whiptongue Frog gains flying until end of turn.

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.)

Tatsunari, Toad Rider

Whenever you cast an enchantment spell, if you don't control a creature named Keimi, create Keimi, a legendary 3/3 black and green Frog creature token with "Whenever you cast an enchantment spell, each opponent loses 1 life and you gain 1 life."
{1}{G/U}: Tatsunari, Toad Rider and target Frog you control can't be blocked this turn except by creatures with flying or reach.

Druidic Ritual

You may mill three cards. Then return up to one creature card and up to one land card from your graveyard to your hand. (To mill a card, put the top card of your library into your graveyard.)

Demonic Stench

Each creature that blocked this turn gets -1/-1 until end of turn. (Then exile this card. You may cast the creature later from exile.)

Hezrou

Whenever one or more creatures you control become blocked, each blocking creature gets -1/-1 until end of turn.

Hezrou // Demonic Stench

Fall from Favor

Enchant creature
When Fall from Favor enters, tap enchanted creature and you become the monarch.
Enchanted creature doesn't untap during its controller's untap step unless that player is the monarch.

Bloated Toad

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

Incongruity

Exile target creature. That creature's controller creates a 3/3 green Frog Lizard creature token.

Incubation

Look at the top five cards of your library. 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 a random order.

Incubation // Incongruity

Shielding Plax

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

Ellywick Tumblestrum

+1: Venture into the dungeon. (Enter the first room or advance to the next room.)
−2: Look at the top six cards of your library. You may reveal a creature card from among them and put it into your hand. If it's legendary, you gain 3 life. Put the rest on the bottom of your library in a random order.
−7: You get an emblem with "Creatures you control have trample and haste and get +2/+2 for each differently named dungeon you've completed."

Binding the Old Gods

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Destroy target nonland permanent an opponent controls.
II — Search your library for a Forest card, put it onto the battlefield tapped, then shuffle.
III — Creatures you control gain deathtouch until end of turn.

Thassa's Emissary

Bestow {5}{U} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached to a creature.)
Whenever Thassa's Emissary or enchanted creature deals combat damage to a player, draw a card.
Enchanted creature gets +3/+3.

Forest

Leapfrog

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

Noxious Toad

When Noxious Toad dies, each opponent discards a card.

Bident of Thassa

Whenever a creature you control deals combat damage to a player, you may draw a card.
{1}{U}, {T}: Creatures your opponents control attack this turn if able.

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.

Spore Frog

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

Alchemist's Refuge

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

Excavating Anurid

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

Anurid Barkripper

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

Galloping Lizrog

Trample
When Galloping Lizrog 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 Galloping Lizrog.

Eel Umbra

Flash (You may cast this spell any time you could cast an instant.)
Enchant creature
Enchanted creature gets +1/+1.
Umbra armor (If enchanted creature would be destroyed, instead remove all damage from it and destroy this Aura.)

Leeching Lurker

Lifelink
Nightbound (If a player casts at least two spells during their own turn, it becomes day next turn.)

Curse of Leeches

Enchant player
As this permanent transforms into Curse of Leeches, attach it to a player.
At the beginning of enchanted player's upkeep, they lose 1 life and you gain 1 life.
Daybound (If a player casts no spells during their own turn, it becomes night next turn.)

Curse of Leeches // Leeching Lurker

Swamp

Pollywog Symbiote

Each creature spell you cast costs {1} less to cast if it has mutate.
Whenever you cast a creature spell, if it has mutate, draw a card, then discard a card.

Frogmite

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

Witch's Familiar

Frog Tongue

Enchant creature
When Frog Tongue enters, draw a card.
Enchanted creature has reach. (It can block creatures with flying.)

Endless Evil

Enchant creature you control
At the beginning of your upkeep, create a token that's a copy of enchanted creature, except the token is 1/1.
When enchanted creature dies, if that creature was a Horror, return Endless Evil to its owner's hand.

Anurid Scavenger

Protection from black
At the beginning of your upkeep, sacrifice Anurid Scavenger unless you put a card from your graveyard on the bottom of your library.

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.

Island

Species Gorger

At the beginning of your upkeep, return a creature you control to its owner's hand.

Rapid Hybridization

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

Seal of Primordium

Sacrifice Seal of Primordium: Destroy target artifact or enchantment.

Omnibian

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

Wild Growth

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

Combat Research

Enchant creature
Enchanted creature has "Whenever this creature deals combat damage to a player, draw a card."
As long as enchanted creature is legendary, it gets +1/+1 and has ward {1}. (Whenever enchanted creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {1}.)

Uurg, Spawn of Turg

Uurg, Spawn of Turg's power is equal to the number of land cards in your graveyard.
At the beginning of your upkeep, surveil 1. (Look at the top card of your library. You may put that card into your graveyard.)
{B}{G}, Sacrifice a land: You gain 2 life.

Leyline of Anticipation

If Leyline of Anticipation is in your opening hand, you may begin the game with it on the battlefield.
You may cast spells as though they had flash.

Anurid Murkdiver

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)

Mercurial Transformation

Until end of turn, target nonland permanent loses all abilities and becomes your choice of a blue Frog creature with base power and toughness 1/1 or a blue Octopus creature with base power and toughness 4/4.

The Gitrog Monster

Deathtouch
At the beginning of your upkeep, sacrifice The Gitrog Monster unless you sacrifice a land.
You may play an additional land on each of your turns.
Whenever one or more land cards are put into your graveyard from anywhere, 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.)

Biomass Mutation

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

Papercraft Decoy

When Papercraft Decoy leaves the battlefield, you may pay {2}. If you do, draw a card.

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.)

Cavern Lampad

Bestow {5}{B} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached to a creature.)
Intimidate (This creature can't be blocked except by artifact creatures and/or creatures that share a color with it.)
Enchanted creature gets +2/+2 and has intimidate.