Have

Infiltrate

Target creature can't be blocked this turn.

Demonic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Swamp

Divination

Havengul Skaab

Whenever Havengul Skaab attacks, return another creature you control to its owner's hand.

Clone

You may have Clone enter the battlefield as a copy of any creature on the battlefield.

Umbris, Fear Manifest

Umbris, Fear Manifest gets +1/+1 for each card your opponents own in exile.
Whenever Umbris or another Nightmare or Horror enters the battlefield under your control, target opponent exiles cards from the top of their library until they exile a land card.

Dimir Aqueduct

Dimir Aqueduct enters the battlefield tapped.
When Dimir Aqueduct enters the battlefield, return a land you control to its owner's hand.
{T}: Add {U}{B}.

Prismatic Lens

{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Ashiok, Nightmare Muse

+1: Create a 2/3 blue and black Nightmare creature token with "Whenever this creature attacks or blocks, each opponent exiles the top two cards of their library."
−3: Return target nonland permanent to its owner's hand, then that player exiles a card from their hand.
−7: You may cast up to three spells from among face-up cards your opponents own from exile without paying their mana costs.

Corrupted Harvester

{B}, Sacrifice a creature: Regenerate Corrupted Harvester.

Wingcrafter

Soulbond (You may pair this creature with another unpaired creature when either enters the battlefield. They remain paired for as long as you control both of them.)
As long as Wingcrafter is paired with another creature, both creatures have flying.

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 of your library.)

Grim Tutor

Search your library for a card, put that card into your hand, then shuffle. You lose 3 life.

Joven's Tools

{4}, {T}: Target creature can't be blocked this turn except by Walls.

Brawler's Plate

Equipped creature gets +2/+2 and has trample. (It can deal excess combat damage to the player or planeswalker it's attacking.)
Equip {4} ({4}: Attach to target creature you control. Equip only as a sorcery.)

Ghostform

Up to two target creatures can't be blocked this turn.

Firemind Vessel

Firemind Vessel enters the battlefield tapped.
{T}: Add two mana of different colors.

Eternal Thirst

Enchant creature
Enchanted creature has lifelink and "Whenever a creature an opponent controls dies, put a +1/+1 counter on this creature." (Damage dealt by a creature with lifelink also causes its controller to gain that much life.)

Disentomb

Return target creature card from your graveyard to your hand.

Jet Medallion

Black spells you cast cost {1} less to cast.

First-Sphere Gargantua

When First-Sphere Gargantua enters the battlefield, you draw a card and you lose 1 life.
Unearth {2}{B} ({2}{B}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Sol Ring

Hunted Nightmare

Menace
When Hunted Nightmare enters the battlefield, target opponent puts a deathtouch counter on a creature they control.

Ashiok's Skulker

{3}{U}: Ashiok's Skulker can't be blocked this turn.

Disappear

Enchant creature
{U}: Return enchanted creature and Disappear to their owners' hands.

Inspiration

Neurok Hoversail

Equipped creature has flying.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery. This card enters the battlefield unattached and stays on the battlefield if the creature leaves.)

Soul Salvage

Return up to two target creature cards from your graveyard to your hand.

Supernatural Stamina

Until end of turn, target creature gets +2/+0 and gains "When this creature dies, return it to the battlefield tapped under its owner's control."

Dimir Signet

Doom Weaver

Reach
Soulbond (You may pair this creature with another unpaired creature when either enters the battlefield. They remain paired for as long as you control both of them.)
As long as Doom Weaver is paired with another creature, each of those creatures has "When this creature dies, draw cards equal to its power."

Island

Cartouche of Knowledge

Enchant creature you control
When Cartouche of Knowledge enters the battlefield, draw a card.
Enchanted creature gets +1/+1 and has flying.

Swimmer in Nightmares

Swimmer in Nightmares gets +3/+0 as long as there are ten or more cards in a single graveyard.
Swimmer in Nightmares can't be blocked as long as you control an Ashiok planeswalker.

Darksteel Ingot

Indestructible (Effects that say "destroy" don't destroy this artifact.)
{T}: Add one mana of any color.

Evolving Wilds

{T}, Sacrifice Evolving Wilds: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Unsummon

Return target creature to its owner's hand.

Tormod's Crypt

{T}, Sacrifice Tormod's Crypt: Exile target player's graveyard.

Dreadwurm

Landfall — Whenever a land enters the battlefield under your control, Dreadwurm gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Kasmina's Transmutation

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

Overcharged Amalgam

Flash
Flying
Exploit (When this creature enters the battlefield, you may sacrifice a creature.)
When Overcharged Amalgam exploits a creature, counter target spell, activated ability, or triggered ability.

Awoken Horror

When this creature transforms into Awoken Horror, return all non-Horror creatures to their owners' hands.

Thing in the Ice

Defender
Thing in the Ice enters the battlefield with four ice counters on it.
Whenever you cast an instant or sorcery spell, remove an ice counter from Thing in the Ice. Then if it has no ice counters on it, transform it.

Thing in the Ice // Awoken Horror

Nephalia Drownyard

{T}: Add {C}.
{1}{U}{B}, {T}: Target player mills three cards.

Grell Philosopher

Aberrant Tinkering — When Grell Philosopher enters the battlefield and at the beginning of your upkeep, each Horror you control gains all activated abilities of target artifact an opponent controls until end of turn. You may spend blue mana as though it were mana of any color to activate those abilities.

Grimdancer

Grimdancer enters the battlefield with your choice of two different counters on it from among menace, deathtouch, and lifelink.

Darkwater Catacombs

Woe Strider

When Woe Strider enters the battlefield, create a 0/1 white Goat creature token.
Sacrifice another creature: Scry 1.
Escape—{3}{B}{B}, Exile four other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.)
Woe Strider escapes with two +1/+1 counters on it.

Rite of Undoing

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Return target nonland permanent you control and target nonland permanent you don't control to their owners' hands.

Dismal Backwater

Dismal Backwater enters the battlefield tapped.
When Dismal Backwater enters the battlefield, you gain 1 life.
{T}: Add {U} or {B}.

Vampiric Tutor

Search your library for a card, then shuffle and put that card on top. You lose 2 life.

Hedron Archive

{T}: Add {C}{C}.
{2}, {T}, Sacrifice Hedron Archive: Draw two cards.

Seer's Lantern

{T}: Add {C}.
{2}, {T}: Scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)

Gateway Plaza

Gateway Plaza enters the battlefield tapped.
When Gateway Plaza enters the battlefield, sacrifice it unless you pay {1}.
{T}: Add one mana of any color.

Arcane Signet

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

Screaming Swarm

Flying
Whenever you attack with one or more creatures, target player mills that many cards. (To mill a card, a player puts the top card of their library into their graveyard.)
{2}{U}: Put Screaming Swarm from your graveyard into your library second from the top.

Murder

Diabolic Tutor

Nighthowler

Bestow {2}{B}{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.)
Nighthowler and enchanted creature each get +X/+X, where X is the number of creature cards in all graveyards.

Darkslick Shores

Darkslick Shores enters the battlefield tapped unless you control two or fewer other lands.
{T}: Add {U} or {B}.

Intervene

Counter target spell that targets a creature.

Chariot of Victory

Equipped creature has first strike, trample, and haste.
Equip {1}

Gravedigger

When Gravedigger enters the battlefield, you may return target creature card from your graveyard to your hand.

Foul Watcher

Flying
When Foul Watcher enters the battlefield, surveil 1. (Look at the top card of your library. You may put that card into your graveyard.)
Delirium — Foul Watcher gets +1/+0 as long as there are four or more card types among cards in your graveyard.

Dread Presence

Whenever a Swamp enters the battlefield under your control, choose one —
• You draw a card and you lose 1 life.
• Dread Presence deals 2 damage to any target and you gain 2 life.

Unlikely Aid

Target creature gets +2/+0 and gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Distant Melody

Choose a creature type. Draw a card for each permanent you control of that type.

Snap

Return target creature to its owner's hand. Untap up to two lands.

Ashiok's Reaper

Whenever an enchantment you control is put into a graveyard from the battlefield, draw a card.

Dead Man's Chest

Enchant creature an opponent controls
When enchanted creature dies, exile cards equal to its power from the top of its owner's library. You may cast spells from among those cards for as long as they remain exiled, and mana of any type can be spent to cast them.

Underworld Charger

Underworld Charger can't block.
Escape—{4}{B}, Exile three other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.)
Underworld Charger escapes with two +1/+1 counters on it.