Partner with Pako, Arcane Retriever (When this creature enters, target player may put Pako into their hand from their library, then shuffle.)

You may play lands and cast noncreature spells from among cards you exiled that have fetch counters on them, and you may spend mana as though it were mana of any color to cast those spells.

Flying

Hellbent — Whenever Headless Specter deals combat damage to a player, if you have no cards in hand, that player discards a card at random.

Hidden Courtyard enters tapped.

: Add .

, , Sacrifice Hidden Courtyard: Discover 4. Activate only as a sorcery. (Exile cards from the top of your library until you exile a nonland card with mana value 4 or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)

Hidden Nursery enters tapped.

: Add .

, , Sacrifice Hidden Nursery: Discover 4. Activate only as a sorcery. (Exile cards from the top of your library until you exile a nonland card with mana value 4 or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)

Target player reveals their hand. That player discards all nonland cards with the same name as another card in their hand.

At the beginning of your upkeep, if you have no cards in hand, each opponent loses 2 life.

At the beginning of each opponent's upkeep, if that player has no cards in hand, they lose 2 life.

Hideaway 4 (When this land enters, look at the top four cards of your library, exile one face down, then put the rest on the bottom in a random order.)

Howltooth Hollow enters tapped.

: Add .

, : You may play the exiled card without paying its mana cost if each player has no cards in hand.

During turns other than yours, this spell costs more to cast.

Return all nonland permanents to their owners' hands. End the turn. (Exile all spells and abilities from the stack, including this card. The player whose turn it is discards down to their maximum hand size. Damage wears off, and "this turn" and "until end of turn" effects end.)

Flying

When Hypnox enters, if you cast it from your hand, exile all cards from target opponent's hand.

When Hypnox leaves the battlefield, return the exiled cards to their owner's hand.

Mutate (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)

Flying, trample

Whenever this creature mutates, exile cards from the top of your library until you exile a nonland permanent card. Put that card onto the battlefield or into your hand.

Reveal a card from your hand. Search your library for a card with the same name as that card, reveal it, put it into your hand, then shuffle.

Hellbent — If you have no cards in hand, instead search your library for a card, put it into your hand, then shuffle.

Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)

Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)

+1: Until your next turn, whenever a creature an opponent controls attacks, it gets -1/-0 until end of turn.

−2: Reveal the top three cards of your library. An opponent separates those cards into two piles. Put one pile into your hand and the other on the bottom of your library in any order.

−8: For each player, search that player's library for a nonland card and exile it, then that player shuffles. You may cast those cards without paying their mana costs.

Whenever Jagged Poppet is dealt damage, discard that many cards.

Hellbent — Whenever Jagged Poppet deals combat damage to a player, if you have no cards in hand, that player discards cards equal to the damage.

Legendary creatures you control get +X/+X, where X is the number of legendary creatures you control.

Whenever you cast a legendary spell from your hand, exile cards from the top of your library until you exile a legendary nonland card with lesser mana value. You may cast that card without paying its mana cost. Put the rest on the bottom of your library in a random order.

+4: Target player exiles a card from their hand.

−3: Exile target permanent.

−14: Restart the game, leaving in exile all non-Aura permanent cards exiled with Karn Liberated. Then put those cards onto the battlefield under your control.

+1: Put a ghostform counter on up to one target nontoken creature. It gains "When this creature dies or is put into exile, return it to its owner's hand and create a 1/1 white Spirit creature token with flying."

−3: Exile target nonland permanent.

−7: You get an emblem with "At the beginning of your upkeep, you may cast a legendary spell from your hand, from your graveyard, or from among cards you own in exile without paying its mana cost."

: Exile the top card of your library. If it's a land card, put it into your hand. Otherwise, put a study counter on it.

: Create a 0/0 green and blue Fractal creature token. Put a +1/+1 counter on it for each different mana value among nonland cards you own in exile with study counters on them.

Imprint — When Knowledge Pool enters, each player exiles the top three cards of their library.

Whenever a player casts a spell from their hand, that player exiles it. If the player does, they may cast a spell from among other cards exiled with Knowledge Pool without paying its mana cost.

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.

Hexproof (This creature can't be the target of spells or abilities your opponents control.)

Whenever Lone Revenant deals combat damage to a player, if you control no other creatures, look at the top four cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.

Lupine Prototype can't attack or block unless a player has no cards in hand.

Reveal the top ten cards of your library. Starting with the next opponent in turn order, each opponent chooses a different nonland card from among them. Put the chosen cards into your hand and the rest on the bottom of your library in a random order.

When Marina Vendrell's Grimoire enters, if you cast it, draw five cards.

You have no maximum hand size and don't lose the game for having 0 or less life.

Whenever you gain life, draw that many cards.

Whenever you lose life, discard that many cards. Then if you have no cards in hand, you lose the game.

Target opponent reveals their hand. You choose a nonland card from it. That player discards that card. You may put a card that has an Adventure that player owns from exile into that player's graveyard.

At the beginning of your upkeep, draw a card if you had no cards in hand at the beginning of this turn. If you had a card in hand, Mindstorm Crown deals 1 damage to you.

+2: Draw two cards, then put a card from your hand on the bottom of your library.

−2: Create a blue Dog Illusion creature token with "This creature's power and toughness are each equal to twice the number of cards in your hand."

−10: Exchange your hand and library, then shuffle. You get an emblem with "You have no maximum hand size."

Each opponent can't draw more than one card each turn.

−2: Look at the top four cards of your library. You may reveal a noncreature, nonland card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Flying

Hellbent — Necromancer's Familiar has lifelink as long as you have no cards in hand.

, Discard a card: Necromancer's Familiar gains indestructible until end of turn. Tap it.

First strike

Other Minotaurs you control have first strike.

As long as you have one or fewer cards in hand, Minotaurs you control get +2/+0.

Whenever Neheb, the Worthy deals combat damage to a player, each player discards a card.

This spell can't be countered.

You have no maximum hand size.

Whenever an opponent casts a noncreature spell, draw a card.

Discard three cards: Exile Nezahal, Primal Tide. Return it to the battlefield tapped under its owner's control at the beginning of the next end step.

Flash

When Niambi, Esteemed Speaker enters, you may return another target creature you control to its owner's hand. If you do, you gain life equal to that creature's mana value.

, , Discard a legendary card: Draw two cards.

, Discard a card: Target opponent loses 1 life and you gain 1 life.

Hellbent — , Pay 2 life: Draw a card. Activate only if you have no cards in hand.

Ninjutsu (, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)

Whenever Okiba-Gang Shinobi deals combat damage to a player, that player discards two cards.

Whenever Pantlaza, Sun-Favored or another Dinosaur you control enters, you may discover X, where X is that creature's toughness. Do this only once each turn. (Exile cards from the top of your library until you exile a nonland card with that mana value or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)

Target opponent reveals their hand. You choose a nonland card from it and exile that card.

Delirium — If there are four or more card types among cards in your graveyard, search that player's graveyard, hand, and library for any number of cards with the same name as the exiled card, exile those cards, then that player shuffles.

Surveil 3 if you have no cards in hand. Then draw three cards. (To surveil 3, look at the top three cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Plot (You may pay and exile this card from your hand. Cast it as a sorcery on a later turn without paying its mana cost. Plot only as a sorcery.)

When Primordial Gnawer dies, discover 3. (Exile cards from the top of your library until you exile a nonland card with mana value 3 or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)

Whenever an opponent discards a card, you may put a quest counter on Quest for the Nihil Stone.

At the beginning of each opponent's upkeep, if that player has no cards in hand and Quest for the Nihil Stone has two or more quest counters on it, you may have that player lose 5 life.

Hellbent — , Sacrifice a creature or land: Draw a card. Activate only if you have no cards in hand.

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

Suspend 2— (Rather than cast this card from your hand, pay and exile it with two time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)

Return all enchantment cards from your graveyard to the battlefield. (Auras with nothing to enchant remain in your graveyard.)

Sage of Ancient Lore's power and toughness are each equal to the number of cards in your hand.

When Sage of Ancient Lore enters, draw a card.

At the beginning of each upkeep, if no spells were cast last turn, transform Sage of Ancient Lore.

+1: Until end of turn, Sarkhan, the Dragonspeaker becomes a legendary 4/4 red Dragon creature with flying, indestructible, and haste. (He doesn't lose loyalty while he's not a planeswalker.)

−3: Sarkhan, the Dragonspeaker deals 4 damage to target creature.

−6: You get an emblem with "At the beginning of your draw step, draw two additional cards" and "At the beginning of your end step, discard your hand."

: Add . ( represents colorless mana.)

, : Draw a card. Activate only if you have no cards in hand.

Exile target nonland card from your graveyard. Search your library for any number of cards with the same name as that card, reveal them, put them into your hand, then shuffle.

, , Return Shigeki, Jukai Visionary to its owner's hand: Reveal the top four cards of your library. You may put a land card from among them onto the battlefield tapped. Put the rest into your graveyard.

Channel — , Discard Shigeki: Return X target nonlegendary cards from your graveyard to your hand.

Reach

Whenever Six attacks, mill three cards. You may put a land card from among them into your hand.

During your turn, nonland permanent cards in your graveyard have retrace. (You may cast permanent cards from your graveyard by discarding a land card in addition to paying their other costs.)

When Slayer's Bounty enters the battlefield, look at the creature cards in target opponent's hand.

Whenever you sacrifice Slayer's Bounty or another Clue, draft a card from Slayer's Bounty's spellbook.

, Sacrifice Slayer's Bounty: Draw a card.

Whenever Smart Ass attacks, choose a card name. If defending player has no cards with the chosen name in their hand, they may reveal their hand. If they don't reveal their hand, Smart Ass can't be blocked this turn.