Hero's Downfall

Niv-Mizzet, the Firemind

Flying
Whenever you draw a card, Niv-Mizzet, the Firemind deals 1 damage to any target.
{T}: Draw a card.

Terrain Generator

{T}: Add {C}.
{2}, {T}: You may put a basic land card from your hand onto the battlefield tapped.

Underworld Dreams

Whenever an opponent draws a card, Underworld Dreams deals 1 damage to that player.

Mountain

Countersquall

Counter target noncreature spell. Its controller loses 2 life.

Kederekt Parasite

Whenever an opponent draws a card, if you control a red permanent, you may have Kederekt Parasite deal 1 damage to that player.

Island

Dismal Backwater

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

Crumbling Necropolis

Crumbling Necropolis enters tapped.
{T}: Add {U}, {B}, or {R}.

Command Tower

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

Terramorphic Expanse

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

Dack Fayden

+1: Target player draws two cards, then discards two cards.
−2: Gain control of target artifact.
−6: You get an emblem with "Whenever you cast a spell that targets one or more permanents, gain control of those permanents."

Foreboding Ruins

As Foreboding Ruins enters, you may reveal a Swamp or Mountain card from your hand. If you don't, Foreboding Ruins enters tapped.
{T}: Add {B} or {R}.

Vile Consumption

All creatures have "At the beginning of your upkeep, sacrifice this creature unless you pay 1 life."

Exquisite Blood

Whenever an opponent loses life, you gain that much life.

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Avatar of Woe

If there are ten or more creature cards total in all graveyards, this spell costs {6} less to cast.
Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
{T}: Destroy target creature. It can't be regenerated.

Wayfarer's Bauble

{2}, {T}, Sacrifice Wayfarer's Bauble: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Stranglehold

Your opponents can't search libraries.
If an opponent would begin an extra turn, that player skips that turn instead.

Neurok Stealthsuit

Equipped creature has shroud. (It can't be the target of spells or abilities.)
{U}{U}: Attach Neurok Stealthsuit to target creature you control.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Frozen Aether

Artifacts, creatures, and lands your opponents control enter tapped.

Mogis, God of Slaughter

Indestructible
As long as your devotion to black and red is less than seven, Mogis isn't a creature.
At the beginning of each opponent's upkeep, Mogis deals 2 damage to that player unless they sacrifice a creature of their choice.

Nicol Bolas, Planeswalker

+3: Destroy target noncreature permanent.
−2: Gain control of target creature.
−9: Nicol Bolas, Planeswalker deals 7 damage to target player or planeswalker. That player or that planeswalker's controller discards seven cards, then sacrifices seven permanents of their choice.

Forced Fruition

Whenever an opponent casts a spell, that player draws seven cards.

Frostboil Snarl

As Frostboil Snarl enters, you may reveal an Island or Mountain card from your hand. If you don't, Frostboil Snarl enters tapped.
{T}: Add {U} or {R}.

Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

Evolving Wilds

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

Iron Maiden

At the beginning of each opponent's upkeep, Iron Maiden deals X damage to that player, where X is the number of cards in their hand minus 4.

Bojuka Bog

Bojuka Bog enters tapped.
When Bojuka Bog enters, exile target player's graveyard.
{T}: Add {B}.

Choked Estuary

As Choked Estuary enters, you may reveal an Island or Swamp card from your hand. If you don't, Choked Estuary enters tapped.
{T}: Add {U} or {B}.

Rakdos Charm

Choose one —
• Exile target player's graveyard.
• Destroy target artifact.
• Each creature deals 1 damage to its controller.

Fevered Visions

At the beginning of each player's end step, that player draws a card. If the player is your opponent and has four or more cards in hand, Fevered Visions deals 2 damage to that player.

Izzet Signet

Damnation

Destroy all creatures. They can't be regenerated.

Jace Beleren

+2: Each player draws a card.
−1: Target player draws a card.
−10: Target player mills twenty cards.

Arcane Denial

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep.
You draw a card at the beginning of the next turn's upkeep.

Fate Unraveler

Whenever an opponent draws a card, Fate Unraveler deals 1 damage to that player.

Swiftwater Cliffs

Swiftwater Cliffs enters tapped.
When Swiftwater Cliffs enters, you gain 1 life.
{T}: Add {U} or {R}.

Breathstealer's Crypt

If a player would draw a card, instead they draw a card and reveal it. If it's a creature card, that player discards it unless they pay 3 life.

Pendrell Mists

All creatures have "At the beginning of your upkeep, sacrifice this creature unless you pay {1}."

Erebos, God of the Dead

Indestructible
As long as your devotion to black is less than five, Erebos isn't a creature. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)
Your opponents can't gain life.
{1}{B}, Pay 2 life: Draw a card.

Deadly Tempest

Destroy all creatures. Each player loses life equal to the number of creatures they controlled that were destroyed this way.

Viseling

At the beginning of each opponent's upkeep, Viseling deals X damage to that player, where X is the number of cards in their hand minus 4.

Spell Crumple

Counter target spell. If that spell is countered this way, put it on the bottom of its owner's library instead of into that player's graveyard. Put Spell Crumple on the bottom of its owner's library.

Phyrexian Tyranny

Whenever a player draws a card, that player loses 2 life unless they pay {2}.

Darksteel Ingot

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

Undermine

Counter target spell. Its controller loses 3 life.

Ob Nixilis Reignited

+1: You draw a card and you lose 1 life.
−3: Destroy target creature.
−8: Target opponent gets an emblem with "Whenever a player draws a card, you lose 2 life."

Vona's Hunger

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
Each opponent sacrifices a creature of their choice. If you have the city's blessing, instead each opponent sacrifices half the creatures they control of their choice, rounded up.

Sulfur Falls

Sulfur Falls enters tapped unless you control an Island or a Mountain.
{T}: Add {U} or {R}.

Jaya, Venerated Firemage

If another red source you control would deal damage to a permanent or player, it deals that much damage plus 1 to that permanent or player instead.
−2: Jaya, Venerated Firemage deals 2 damage to any target.

Ob Nixilis, the Hate-Twisted

Whenever an opponent draws a card, Ob Nixilis, the Hate-Twisted deals 1 damage to that player.
−2: Destroy target creature. Its controller draws two cards.

Nekusar, the Mindrazer

At the beginning of each player's draw step, that player draws an additional card.
Whenever an opponent draws a card, Nekusar, the Mindrazer deals 1 damage to that player.

Monastery Siege

As Monastery Siege enters, choose Khans or Dragons.
• Khans — At the beginning of your draw step, draw an additional card, then discard a card.
• Dragons — Spells your opponents cast that target you or a permanent you control cost {2} more to cast.

Thought Vessel

Crypt Incursion

Exile all creature cards from target player's graveyard. You gain 3 life for each card exiled this way.

Dragonskull Summit

Dragonskull Summit enters tapped unless you control a Swamp or a Mountain.
{T}: Add {B} or {R}.

Lightning Greaves

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

Torpor Orb

Creatures entering don't cause abilities to trigger.

Teferi's Puzzle Box

At the beginning of each player's draw step, that player puts the cards in their hand on the bottom of their library in any order, then draws that many cards.

Cyclonic Rift

Return target nonland permanent you don't control to its owner's hand.
Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Tainted Aether

Whenever a creature enters, its controller sacrifices a creature or land of their choice.

Reforge the Soul

Each player discards their hand, then draws seven cards.
Miracle {1}{R} (You may cast this card for its miracle cost when you draw it if it's the first card you drew this turn.)

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Psychosis Crawler

Psychosis Crawler's power and toughness are each equal to the number of cards in your hand.
Whenever you draw a card, each opponent loses 1 life.

Spiteful Visions

At the beginning of each player's draw step, that player draws an additional card.
Whenever a player draws a card, Spiteful Visions deals 1 damage to that player.

Alexi's Cloak

Flash
Enchant creature
Enchanted creature has shroud. (It can't be the target of spells or abilities.)

Swamp

Drowned Catacomb

Drowned Catacomb enters tapped unless you control an Island or a Swamp.
{T}: Add {U} or {B}.

Liliana's Caress

Whenever an opponent discards a card, that player loses 2 life.

Counterspell

Kira, Great Glass-Spinner

Flying
Creatures you control have "Whenever this creature becomes the target of a spell or ability for the first time each turn, counter that spell or ability."

Dimir Signet

Commander's Sphere

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

Bloodfell Caves

Bloodfell Caves enters tapped.
When Bloodfell Caves enters, you gain 1 life.
{T}: Add {B} or {R}.

Basilisk Collar

Equipped creature has deathtouch and lifelink.
Equip {2}

Megrim

Whenever an opponent discards a card, Megrim deals 2 damage to that player.

Grixis Panorama

{T}: Add {C}.
{1}, {T}, Sacrifice Grixis Panorama: Search your library for a basic Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Terminate

Destroy target creature. It can't be regenerated.

Ghost Quarter

{T}: Add {C}.
{T}, Sacrifice Ghost Quarter: Destroy target land. Its controller may search their library for a basic land card, put it onto the battlefield, then shuffle.

Archfiend of Depravity

Flying
At the beginning of each opponent's end step, that player chooses up to two creatures they control, then sacrifices the rest.

Rakdos Signet

Sol Ring

Crosis's Charm

Choose one —
• Return target permanent to its owner's hand.
• Destroy target nonblack creature. It can't be regenerated.
• Destroy target artifact.