Midnight Clock

{T}: Add {U}.
{2}{U}: Put an hour counter on Midnight Clock.
At the beginning of each upkeep, put an hour counter on Midnight Clock.
When the twelfth hour counter is put on Midnight Clock, shuffle your hand and graveyard into your library, then draw seven cards. Exile Midnight Clock.

Infinite Hourglass

At the beginning of your upkeep, put a time counter on Infinite Hourglass.
All creatures get +1/+0 for each time counter on Infinite Hourglass.
{3}: Remove a time counter from Infinite Hourglass. Any player may activate this ability but only during any upkeep step.

Ashnod the Uncaring

Deathtouch
Whenever you activate an ability of an artifact or creature that isn't a mana ability, if one or more permanents were sacrificed to activate it, you may copy that ability. You may choose new targets for the copy. (Sacrificing an artifact for mana to activate an ability doesn't count.)

Herald of Leshrac

Flying
Cumulative upkeep—Gain control of a land you don't control. (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
Herald of Leshrac gets +1/+1 for each land you control but don't own.
When Herald of Leshrac leaves the battlefield, each player gains control of each land they own that you control.

Drowned Catacomb

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

Mystic Remora

Cumulative upkeep {1} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
Whenever an opponent casts a noncreature spell, you may draw a card unless that player pays {4}.

Morphic Pool

Morphic Pool enters the battlefield tapped unless you have two or more opponents.
{T}: Add {U} or {B}.

Mechanized Production

Enchant artifact you control
At the beginning of your upkeep, create a token that's a copy of enchanted artifact. Then if you control eight or more artifacts with the same name as one another, you win the game.

Bojuka Bog

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

Sulfurous Springs

{T}: Add {C}.
{T}: Add {B} or {R}. Sulfurous Springs deals 1 damage to you.

Clearwater Goblet

Sunburst (This enters the battlefield with a charge counter on it for each color of mana spent to cast it.)
At the beginning of your upkeep, you may gain life equal to the number of charge counters on Clearwater Goblet.

Exotic Orchard

{T}: Add one mana of any color that a land an opponent controls could produce.

Ring of Evos Isle

{2}: Equipped creature gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)
At the beginning of your upkeep, put a +1/+1 counter on equipped creature if it's blue.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Golden Urn

At the beginning of your upkeep, you may put a charge counter on Golden Urn.
{T}, Sacrifice Golden Urn: You gain life equal to the number of charge counters on Golden Urn.

River Song's Diary

Imprint — Whenever a player casts an instant or sorcery spell from their hand, exile it instead of putting it into a graveyard as it resolves.
At the beginning of your upkeep, if there are four or more cards exiled with River Song's Diary, choose one of them at random. You may cast it without paying its mana cost.

Manifold Key

{1}, {T}: Untap another target artifact.
{3}, {T}: Target creature can't be blocked this turn.

Energy Chamber

At the beginning of your upkeep, choose one —
• Put a +1/+1 counter on target artifact creature.
• Put a charge counter on target noncreature artifact.

Silver Shroud Costume

Flash
When Silver Shroud Costume enters the battlefield, attach it to target creature you control. That creature gains shroud until end of turn. (It can't be the target of spells or abilities.)
Equipped creature can't be blocked.
Equip {3}

Heart of Bogardan

Cumulative upkeep {2} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
When a player doesn't pay Heart of Bogardan's cumulative upkeep, Heart of Bogardan deals X damage to target player or planeswalker and each creature that player or that planeswalker's controller controls, where X is twice the number of age counters on Heart of Bogardan minus 2.

Shrine of Burning Rage

At the beginning of your upkeep or whenever you cast a red spell, put a charge counter on Shrine of Burning Rage.
{3}, {T}, Sacrifice Shrine of Burning Rage: It deals damage equal to the number of charge counters on it to any target.

Island

Locus of Enlightenment

Locus of Enlightenment has each activated ability of the exiled cards used to craft it. You may activate each of those abilities only once each turn.
Whenever you activate an ability that isn't a mana ability, copy it. You may choose new targets for the copy.

The Enigma Jewel

The Enigma Jewel enters the battlefield tapped.
{T}: Add {C}{C}. Spend this mana only to activate abilities.
Craft with four or more nonlands with activated abilities {8}{U} ({8}{U}, Exile this artifact, Exile the four or more from among other permanents you control and/or cards in your graveyard: Return this card transformed under its owner's control. Craft only as a sorcery.)

The Enigma Jewel // Locus of Enlightenment

Ashnod's Altar

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Xander's Lounge

({T}: Add {U}, {B}, or {R}.)
Xander's Lounge enters the battlefield tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Luxury Suite

Luxury Suite enters the battlefield tapped unless you have two or more opponents.
{T}: Add {B} or {R}.

Prismite

Scalding Tongs

At the beginning of your upkeep, if you have three or fewer cards in hand, Scalding Tongs deals 1 damage to target opponent or planeswalker.

Karn, Legacy Reforged

Karn, Legacy Reforged's power and toughness are each equal to the greatest mana value among artifacts you control.
At the beginning of your upkeep, add {C} for each artifact you control. This mana can't be spent to cast nonartifact spells. Until end of turn, you don't lose this mana as steps and phases end.

Venser's Journal

You have no maximum hand size.
At the beginning of your upkeep, you gain 1 life for each card in your hand.

Magma Mine

{4}: Put a pressure counter on Magma Mine.
{T}, Sacrifice Magma Mine: It deals damage equal to the number of pressure counters on it to any target.

Whispersilk Cloak

Equipped creature can't be blocked and has shroud. (It can't be the target of spells or abilities.)
Equip {2}

Ring of Xathrid

{2}: Regenerate equipped creature. (The next time that creature would be destroyed this turn, it isn't. Instead tap it, remove all damage from it, and remove it from combat.)
At the beginning of your upkeep, put a +1/+1 counter on equipped creature if it's black.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Thumbscrews

At the beginning of your upkeep, if you have five or more cards in hand, Thumbscrews deals 1 damage to target opponent or planeswalker.

Time Bomb

At the beginning of your upkeep, put a time counter on Time Bomb.
{1}, {T}, Sacrifice Time Bomb: Time Bomb deals damage equal to the number of time counters on it to each creature and each player.

Foundry Inspector

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

Stormcarved Coast

Stormcarved Coast enters the battlefield tapped unless you control two or more other lands.
{T}: Add {U} or {R}.

Thopter Spy Network

At the beginning of your upkeep, if you control an artifact, create a 1/1 colorless Thopter artifact creature token with flying.
Whenever one or more artifact creatures you control deal combat damage to a player, draw a card.

Sol Ring

Ring of Valkas

Equipped creature has haste. (It can attack and {T} no matter when it came under your control.)
At the beginning of your upkeep, put a +1/+1 counter on equipped creature if it's red.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Armageddon Clock

At the beginning of your upkeep, put a doom counter on Armageddon Clock.
At the beginning of your draw step, Armageddon Clock deals damage equal to the number of doom counters on it to each player.
{4}: Remove a doom counter from Armageddon Clock. Any player may activate this ability but only during any upkeep step.

Replicating Ring

{T}: Add one mana of any color.
At the beginning of your upkeep, put a night counter on Replicating Ring. Then if it has eight or more night counters on it, remove all of them and create eight colorless snow artifact tokens named Replicated Ring with "{T}: Add one mana of any color."

Corrosion

Cumulative upkeep {1} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
At the beginning of your upkeep, put a rust counter on each artifact target opponent controls. Then destroy each artifact with mana value less than or equal to the number of rust counters on it. Artifacts destroyed this way can't be regenerated.
When Corrosion leaves the battlefield, remove all rust counters from all permanents.

Padeem, Consul of Innovation

Artifacts you control have hexproof.
At the beginning of your upkeep, if you control the artifact with the highest mana value or tied for the highest mana value, draw a card.

Vedalken Orrery

You may cast spells as though they had flash.

Mindstorm Crown

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.

Dragonspark Reactor

Whenever Dragonspark Reactor or another artifact enters the battlefield under your control, put a charge counter on Dragonspark Reactor.
{4}, Sacrifice Dragonspark Reactor: It deals damage equal to the number of charge counters on it to target player and that much damage to up to one target creature.

Staff of Nin

At the beginning of your upkeep, draw a card.
{T}: Staff of Nin deals 1 damage to any target.

Arcane Signet

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

Jhoira, Weatherlight Captain

Whenever you cast a historic spell, draw a card. (Artifacts, legendaries, and Sagas are historic.)

Sonic Screwdriver

{T}: Add one mana of any color.
{1}, {T}: Untap another target artifact.
{2}, {T}: Scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{3}, {T}: Target creature can't be blocked this turn.

Dragonskull Summit

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

Shivan Reef

{T}: Add {C}.
{T}: Add {U} or {R}. Shivan Reef deals 1 damage to you.

Swamp

Tamiyo's Journal

At the beginning of your upkeep, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")
{T}, Sacrifice three Clues: Search your library for a card, put that card into your hand, then shuffle.

Gemstone Array

{2}: Put a charge counter on Gemstone Array.
Remove a charge counter from Gemstone Array: Add one mana of any color.

Mechanized Warfare

If a red or artifact source you control would deal damage to an opponent or a permanent an opponent controls, it deals that much damage plus 1 instead.

Command Tower

Suspicious Bookcase

Defender
{3}, {T}: Target creature can't be blocked this turn.

Shipwreck Marsh

Shipwreck Marsh enters the battlefield tapped unless you control two or more other lands.
{T}: Add {U} or {B}.

Kyren Archive

At the beginning of your upkeep, you may exile the top card of your library face down.
{5}, Discard your hand, Sacrifice Kyren Archive: Put all cards exiled with Kyren Archive into their owner's hand.

Jhoira's Familiar

Flying
Historic spells you cast cost {1} less to cast. (Artifacts, legendaries, and Sagas are historic.)

Underground River

{T}: Add {C}.
{T}: Add {U} or {B}. Underground River deals 1 damage to you.

Crumbling Necropolis

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

Thran Turbine

At the beginning of your upkeep, you may add {C}{C}. You can't spend this mana to cast spells.

Darksteel Reactor

Indestructible (Effects that say "destroy" don't destroy this artifact.)
At the beginning of your upkeep, you may put a charge counter on Darksteel Reactor.
When Darksteel Reactor has twenty or more charge counters on it, you win the game.

Sulfur Falls

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

Tetravus

Flying
Tetravus enters the battlefield with three +1/+1 counters on it.
At the beginning of your upkeep, you may remove any number of +1/+1 counters from Tetravus. If you do, create that many 1/1 colorless Tetravite artifact creature tokens. They each have flying and "This creature can't be enchanted."
At the beginning of your upkeep, you may exile any number of tokens created with Tetravus. If you do, put that many +1/+1 counters on Tetravus.

Moonsilver Key

{1}, {T}, Sacrifice Moonsilver Key: Search your library for an artifact card with a mana ability or a basic land card, reveal it, put it into your hand, then shuffle.

Reliquary Tower

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

Astral Cornucopia

Astral Cornucopia enters the battlefield with X charge counters on it.
{T}: Choose a color. Add one mana of that color for each charge counter on Astral Cornucopia.

Staff of Compleation

{T}, Pay 1 life: Destroy target permanent you own.
{T}, Pay 2 life: Add one mana of any color.
{T}, Pay 3 life: Proliferate.
{T}, Pay 4 life: Draw a card.
{5}: Untap Staff of Compleation.

Braid of Fire

Cumulative upkeep—Add {R}. (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)

Gate to the Aether

At the beginning of each player's upkeep, that player reveals the top card of their library. If it's an artifact, creature, enchantment, or land card, the player may put it onto the battlefield.

Aether Vial

At the beginning of your upkeep, you may put a charge counter on Aether Vial.
{T}: You may put a creature card with mana value equal to the number of charge counters on Aether Vial from your hand onto the battlefield.

Ivory Tower

At the beginning of your upkeep, you gain X life, where X is the number of cards in your hand minus 4.

Obeka, Splitter of Seconds

Menace
Whenever Obeka, Splitter of Seconds deals combat damage to a player, you get that many additional upkeep steps after this phase.

Haunted Ridge

Haunted Ridge enters the battlefield tapped unless you control two or more other lands.
{T}: Add {B} or {R}.

Training Center

Training Center enters the battlefield tapped unless you have two or more opponents.
{T}: Add {U} or {R}.

Mountain

Flux Channeler

Whenever you cast a noncreature spell, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

All Will Be One

Whenever you put one or more counters on a permanent or player, All Will Be One deals that much damage to target opponent, creature an opponent controls, or planeswalker an opponent controls.

Culling Scales

At the beginning of your upkeep, destroy target nonland permanent with the lowest mana value. (If two or more permanents are tied for lowest, target any one of them.)

Inventors' Fair

At the beginning of your upkeep, if you control three or more artifacts, you gain 1 life.
{T}: Add {C}.
{4}, {T}, Sacrifice Inventors' Fair: Search your library for an artifact card, reveal it, put it into your hand, then shuffle. Activate only if you control three or more artifacts.