Halo Hopper

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)

Commander's Sphere

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

Strategic Planning

Look at the top three cards of your library. Put one of them into your hand and the rest into your graveyard.

Blanchwood Prowler

When Blanchwood Prowler enters, mill three cards. You may put a land card from among the cards milled this way into your hand. If you don't, put a +1/+1 counter on Blanchwood Prowler. (To mill a card, put the top card of your library into your graveyard.)

Wand of Vertebrae

{T}: Mill a card.
{2}, {T}, Exile Wand of Vertebrae: Shuffle up to five target cards from your graveyard into your library.

Traumatize

Target player mills half their library, rounded down.

Universal Automaton

Changeling (This card is every creature type.)

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.)

Codex Shredder

{T}: Target player mills a card. (They put the top card of their library into their graveyard.)
{5}, {T}, Sacrifice Codex Shredder: Return target card from your graveyard to your hand.

Thought Scour

Target player mills two cards.
Draw a card.

Millikin

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

Founding the Third Path

Read ahead (Choose a chapter and start with that many lore counters. Add one after your draw step. Skipped chapters don't trigger. Sacrifice after III.)
I — You may cast an instant or sorcery spell with mana value 1 or 2 from your hand without paying its mana cost.
II — Target player mills four cards.
III — Exile target instant or sorcery card from your graveyard. Copy it. You may cast the copy.

Sarinth Steelseeker

Whenever an artifact you control enters, look at the top card of your library. If it's a land card, you may reveal it and put it into your hand. If you don't put the card into your hand, you may put it into your graveyard.

Venture Deeper

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

Merfolk Secretkeeper

Merfolk Secretkeeper // Venture Deeper

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.

Burrowing Razormaw

When Burrowing Razormaw dies, mill four cards. (Put the top four cards of your library into your graveyard.)

Deranged Assistant

Winds of Rebuke

Return target nonland permanent to its owner's hand. Each player mills two cards.

Skola Grovedancer

Whenever a land card is put into your graveyard from anywhere, you gain 1 life.
{2}{G}: Mill a card. (Put the top card of your library into your graveyard.)

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.

Millstone

Curse of the Bloody Tome

Enchant player
At the beginning of enchanted player's upkeep, that player mills two cards.

Cut Your Losses

Casualty 2 (As you cast this spell, you may sacrifice a creature with power 2 or greater. When you do, copy this spell and you may choose a new target for the copy.)
Target player mills half their library, rounded down.

Druid Class

(Gain the next level as a sorcery to add its ability.)
Landfall — Whenever a land you control enters, you gain 1 life.
{2}{G}: Level 2
You may play an additional land on each of your turns.
{4}{G}: Level 3
When this Class becomes level 3, target land you control becomes a creature with haste and "This creature's power and toughness are each equal to the number of lands you control." It's still a land.

Island

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.

Explore

You may play an additional land this turn.
Draw a card.

Crop Sigil

At the beginning of your upkeep, you may mill a card.
Delirium — {2}{G}, Sacrifice Crop Sigil: Return up to one target creature card and up to one target land card from your graveyard to your hand. Activate only if there are four or more card types among cards in your graveyard.

Fallaji Archaeologist

When Fallaji Archaeologist enters, mill three cards. You may put a noncreature, nonland card from among the cards milled this way into your hand. If you don't, put a +1/+1 counter on Fallaji Archaeologist. (To mill a card, put the top card of your library into your graveyard.)

Turn to Frog

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

Satyr Wayfinder

When Satyr Wayfinder 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.

Willow Geist

Trample
Whenever one or more cards leave your graveyard, put a +1/+1 counter on Willow Geist.
When Willow Geist dies, you gain life equal to its power.

Deathbonnet Hulk

At the beginning of your upkeep, you may exile a card from a graveyard. If a creature card was exiled this way, put a +1/+1 counter on Deathbonnet Hulk.

Deathbonnet Sprout

At the beginning of your upkeep, mill a card. Then if there are three or more creature cards in your graveyard, transform Deathbonnet Sprout. (To mill a card, put the top card of your library into your graveyard.)

Deathbonnet Sprout // Deathbonnet Hulk

Glittering Frost

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

Chronic Flooding

Enchant land
Whenever enchanted land becomes tapped, its controller mills three cards.

Jace, Wielder of Mysteries

If you would draw a card while your library has no cards in it, you win the game instead.
+1: Target player mills two cards. Draw a card.
−8: Draw seven cards. Then if your library has no cards in it, you win the game.

Curate

Surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)
Draw a card.

Perpetual Timepiece

{T}: Mill two cards.
{2}, Exile Perpetual Timepiece: Shuffle any number of target cards from your graveyard into your library.

Wasteful Harvest

Mill five cards. You may put a permanent card from among the cards milled this way into your hand. (To mill a card, put the top card of your library into your graveyard.)

Compelling Argument

Target player mills five cards.
Cycling {U} ({U}, Discard this card: Draw a card.)

Omnibian

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

Rampant Growth

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

Nature's Claim

Destroy target artifact or enchantment. Its controller gains 4 life.

Foundation Breaker

When Foundation Breaker enters, you may destroy target artifact or enchantment.
Evoke {1}{G} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Spore Frog

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

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.)

Mulch

Reveal the top four cards of your library. Put all land cards revealed this way into your hand and the rest into your graveyard.

Wild Growth

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

Haywire Mite

When Haywire Mite dies, you gain 2 life.
{G}, Sacrifice Haywire Mite: Exile target noncreature artifact or noncreature enchantment.

Talisman of Curiosity

{T}: Add {C}.
{T}: Add {G} or {U}. Talisman of Curiosity deals 1 damage to you.

Tome Scour

Reflections of Littjara

As Reflections of Littjara enters, choose a creature type.
Whenever you cast a spell of the chosen type, copy that spell. (A copy of a permanent spell becomes a token.)

Homarid Explorer

When Homarid Explorer enters, target player mills four cards.

Drowned Secrets

Whenever you cast a blue spell, target player mills two cards.

Disturbing Conversion

Flash
Enchant creature
When Disturbing Conversion enters, each player mills two cards.
Enchanted creature gets -X/-0, where X is the number of cards in its controller's graveyard.

Roots of Wisdom

Mill three cards, then return a land card or Elf card from your graveyard to your hand. If you can't, draw a card. (To mill a card, put the top card of your library into your graveyard.)

Fleet Swallower

Whenever Fleet Swallower attacks, target player mills half their library, rounded up.

Elvish Mystic

Jace's Erasure

Whenever you draw a card, you may have target player mill a card.

Jade Avenger

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

Cruel Witness

Flying
Whenever you cast a noncreature spell, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Negate

Cankerbloom

{1}, Sacrifice Cankerbloom: Choose one —
• Destroy target artifact.
• Destroy target enchantment.
• Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)