Obeka, Splitter of Seconds

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

Brotherhood Regalia

Equipped creature has ward {2}, is an Assassin in addition to its other types, and can't be blocked.
Equip legendary creature {1}
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)

Silent Arbiter

No more than one creature can attack each combat.
No more than one creature can block each combat.

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.)

Estrid's Invocation

You may have this enchantment enter as a copy of an enchantment you control, except it has "At the beginning of your upkeep, you may exile this enchantment. If you do, return it to the battlefield under its owner's control."

Toxic Deluge

As an additional cost to cast this spell, pay X life.
All creatures get -X/-X until end of turn.

Indulgent Tormentor

Flying
At the beginning of your upkeep, draw a card unless target opponent sacrifices a creature of their choice or pays 3 life.

Thought Vessel

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

Scrawling Crawler

At the beginning of your upkeep, each player draws a card.
Whenever an opponent draws a card, that player loses 1 life.

Tavern Brawler

Commander creatures you own have "At the beginning of your upkeep, exile the top card of your library. This creature gets +X/+0 until end of turn, where X is that card's mana value. You may play that card this turn."

Creeping Bloodsucker

At the beginning of your upkeep, this creature deals 1 damage to each opponent. You gain life equal to the damage dealt this way.

Mox Tantalite

Suspend 3—{0} (Rather than cast this card from your hand, pay {0} and exile it with three 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.)
{T}: Add one mana of any color.

Have

Blood Crypt

({T}: Add {B} or {R}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.

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.)
This creature gets +1/+1 for each land you control but don't own.
When this creature leaves the battlefield, each player gains control of each land they own that you control.

Skyline Despot

Flying
When this creature enters, you become the monarch.
At the beginning of your upkeep, if you're the monarch, create a 5/5 red Dragon creature token with flying.

Plargg and Nassari

At the beginning of your upkeep, each player exiles cards from the top of their library until they exile a nonland card. An opponent chooses a nonland card exiled this way. You may cast up to two spells from among the other cards exiled this way without paying their mana costs.

Dragonmaster Outcast

At the beginning of your upkeep, if you control six or more lands, create a 5/5 red Dragon creature token with flying.

Arcane Signet

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

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.)

Polluted Delta

{T}, Pay 1 life, Sacrifice this land: Search your library for an Island or Swamp card, put it onto the battlefield, then shuffle.

Paradox Haze

Enchant player
At the beginning of enchanted player's first upkeep each turn, that player gets an additional upkeep step after this step.

Court of Ambition

When this enchantment enters, you become the monarch.
At the beginning of your upkeep, each opponent loses 3 life unless they discard a card. If you're the monarch, instead each opponent loses 6 life unless they discard two cards.

Slip Out the Back

Put a +1/+1 counter on target creature. It phases out. (Treat it and anything attached to it as though they don't exist until its controller's next turn.)

Steam Vents

({T}: Add {U} or {R}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.

Drowned Catacomb

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

Reverse the Polarity

Choose one —
• Counter all other spells.
• Switch each creature's power and toughness until end of turn.
• Creatures can't be blocked this turn.

Endless Evil

Enchant creature you control
At the beginning of your upkeep, create a token that's a copy of enchanted creature, except the token is 1/1.
When enchanted creature dies, if that creature was a Horror, return this card to its owner's hand.

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.)

Xander's Lounge

({T}: Add {U}, {B}, or {R}.)
This land enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Deflecting Swat

If you control a commander, you may cast this spell without paying its mana cost.
You may choose new targets for target spell or ability.

Scalding Tarn

{T}, Pay 1 life, Sacrifice this land: Search your library for an Island or Mountain card, put it onto the battlefield, then shuffle.

As Foretold

At the beginning of your upkeep, put a time counter on this enchantment.
Once each turn, you may pay {0} rather than pay the mana cost for a spell you cast with mana value X or less, where X is the number of time counters on this enchantment.

Jhoira of the Ghitu

{2}, Exile a nonland card from your hand: Put four time counters on the exiled card. If it doesn't have suspend, it gains suspend. (At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost. If it's a creature, it has haste.)

Searstep Pathway

Blightstep Pathway

Blightstep Pathway // Searstep Pathway

Shipwreck Marsh

This land enters tapped unless you control two or more other lands.
{T}: Add {U} or {B}.

The Reaver Cleaver

Equipped creature gets +1/+1 and has trample and "Whenever this creature deals combat damage to a player or planeswalker, create that many Treasure tokens."
Equip {3}

Sulfurous Springs

{T}: Add {C}.
{T}: Add {B} or {R}. This land deals 1 damage to you.

Damnation

Destroy all creatures. They can't be regenerated.

Winged Boots

Equipped creature has flying and ward {4}. (Whenever equipped creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {4}.)
Equip {1}

Aggravated Assault

{3}{R}{R}: Untap all creatures you control. After this main phase, there is an additional combat phase followed by an additional main phase. Activate only as a sorcery.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Frostcliff Siege

As this enchantment enters, choose Jeskai or Temur.
• Jeskai — Whenever one or more creatures you control deal combat damage to a player, draw a card.
• Temur — Creatures you control get +1/+0 and have trample and haste.

Rogue's Passage

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

Sword of Feast and Famine

Equipped creature gets +2/+2 and has protection from black and from green.
Whenever equipped creature deals combat damage to a player, that player discards a card and you untap all lands you control.
Equip {2}

Trailblazer's Boots

Equipped creature has nonbasic landwalk. (It can't be blocked as long as defending player controls a nonbasic land.)
Equip {2}

Astarion's Thirst

Exile target creature. Put X +1/+1 counters on a commander creature you control, where X is the power of the creature exiled this way.

Descent into Avernus

At the beginning of your upkeep, put two descent counters on this enchantment. Then each player creates X Treasure tokens and this enchantment deals X damage to each player, where X is the number of descent counters on this enchantment.

Phyrexian Arena

At the beginning of your upkeep, you draw a card and you lose 1 life.

The Ninth Doctor

Haste
Into the TARDIS — Whenever The Ninth Doctor becomes untapped during your untap step, you get an additional upkeep step after this step.

Cathedral of War

This land enters tapped.
Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)
{T}: Add {C}.

Clout of the Dominus

Enchant creature
As long as enchanted creature is blue, it gets +1/+1 and has shroud. (It can't be the target of spells or abilities.)
As long as enchanted creature is red, it gets +1/+1 and has haste.

Call of the Ring

At the beginning of your upkeep, the Ring tempts you.
Whenever you choose a creature as your Ring-bearer, you may pay 2 life. If you do, draw a card.

Blasphemous Act

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

Shizo, Death's Storehouse

{T}: Add {B}.
{B}, {T}: Target legendary creature gains fear until end of turn. (It can't be blocked except by artifact creatures and/or black creatures.)

Blazemire Verge

{T}: Add {B}.
{T}: Add {R}. Activate only if you control a Swamp or a Mountain.

Rhystic Study

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

Palace Siege

As this enchantment enters, choose Khans or Dragons.
• Khans — At the beginning of your upkeep, return target creature card from your graveyard to your hand.
• Dragons — At the beginning of your upkeep, each opponent loses 2 life and you gain 2 life.

Dockside Extortionist

When this creature enters, create X Treasure tokens, where X is the number of artifacts and enchantments your opponents control. (Treasure tokens are artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

Fellwar Stone

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

Security Bypass

Enchant creature
As long as enchanted creature is attacking alone, it can't be blocked.
Enchanted creature has "Whenever this creature deals combat damage to a player, it connives." (Its controller draws a card, then discards a card. If they discarded a nonland card, they put a +1/+1 counter on this creature.)

Bloodstained Mire

{T}, Pay 1 life, Sacrifice this land: Search your library for a Swamp or Mountain card, put it onto the battlefield, then shuffle.

Silver Shroud Costume

Flash
When this Equipment enters, 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}

Watery Grave

({T}: Add {U} or {B}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.

Luxury Suite

This land enters tapped unless you have two or more opponents.
{T}: Add {B} or {R}.

Command Tower

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.

Sol Talisman

Suspend 3—{1} (Rather than cast this card from your hand, pay {1} and exile it with three 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.)
{T}: Add {C}{C}.

Caves of Chaos Adventurer

Trample
When this creature enters, you take the initiative.
Whenever this creature attacks, exile the top card of your library. If you've completed a dungeon, you may play that card this turn without paying its mana cost. Otherwise, you may play that card this turn.

The Black Gate

As The Black Gate enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {B}.
{1}{B}, {T}: Choose a player with the most life or tied for most life. Target creature can't be blocked by creatures that player controls this turn.

Sheoldred, Whispering One

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
At the beginning of your upkeep, return target creature card from your graveyard to the battlefield.
At the beginning of each opponent's upkeep, that player sacrifices a creature of their choice.

Rising of the Day

Creatures you control have haste.
Legendary creatures you control get +1/+0.

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.")

Stormcarved Coast

This land enters tapped unless you control two or more other lands.
{T}: Add {U} or {R}.

Embercleave

Flash
This spell costs {1} less to cast for each attacking creature you control.
When Embercleave enters, attach it to target creature you control.
Equipped creature gets +1/+1 and has double strike and trample.
Equip {3}

Underground River

{T}: Add {C}.
{T}: Add {U} or {B}. This land deals 1 damage to you.

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 this artifact.
When this artifact has twenty or more charge counters on it, you win the game.

Karlach, Fury of Avernus

Whenever you attack, if it's the first combat phase of the turn, untap all attacking creatures. They gain first strike until end of turn. After this phase, there is an additional combat phase.
Choose a Background (You can have a Background as a second commander.)

Gloomlake Verge

{T}: Add {U}.
{T}: Add {B}. Activate only if you control an Island or a Swamp.

Sulfur Falls

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

Chaos Warp

The owner of target permanent shuffles it into their library, then reveals the top card of their library. If it's a permanent card, they put it onto the battlefield.

Mountain

Shivan Reef

{T}: Add {C}.
{T}: Add {U} or {R}. This land deals 1 damage to you.

Talisman of Creativity

{T}: Add {C}.
{T}: Add {U} or {R}. This artifact deals 1 damage to you.

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.

Extravagant Replication

At the beginning of your upkeep, create a token that's a copy of another target nonland permanent you control.

Tibalt's Trickery

Counter target spell. Choose 1, 2, or 3 at random. Its controller mills that many cards, then exiles cards from the top of their library until they exile a nonland card with a different name than that spell. They may cast that card without paying its mana cost. Then they put the exiled cards on the bottom of their library in a random order.

Twilight Prophet

Flying
Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
At the beginning of your upkeep, if you have the city's blessing, reveal the top card of your library and put it into your hand. Each opponent loses X life and you gain X life, where X is that card's mana value.

Court of Cunning

When this enchantment enters, you become the monarch.
At the beginning of your upkeep, any number of target players each mill two cards. If you're the monarch, each of those players mills ten cards instead. (To mill a card, a player puts the top card of their library into their graveyard.)

Whispersilk Cloak

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

An Offer You Can't Refuse

Counter target noncreature spell. Its controller creates two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

Replicating Ring

{T}: Add one mana of any color.
At the beginning of your upkeep, put a night counter on this artifact. 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."

Morphic Pool

This land enters tapped unless you have two or more opponents.
{T}: Add {U} or {B}.

Haunted Ridge

This land enters tapped unless you control two or more other lands.
{T}: Add {B} or {R}.

Thassa, God of the Sea

Indestructible
As long as your devotion to blue is less than five, Thassa isn't a creature. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)
At the beginning of your upkeep, scry 1.
{1}{U}: Target creature you control can't be blocked this turn.

Lavaglide Pathway

Riverglide Pathway

Riverglide Pathway // Lavaglide Pathway

Rousing Refrain

Add {R} for each card in target opponent's hand. Until end of turn, you don't lose this mana as steps and phases end. Exile Rousing Refrain with three time counters on it.
Suspend 3—{1}{R} (Rather than cast this card from your hand, you may pay {1}{R} and exile it with three 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.)

Hatred

As an additional cost to cast this spell, pay X life.
Target creature gets +X/+0 until end of turn.

Island

Sin Prodder

Menace
At the beginning of your upkeep, reveal the top card of your library. Any opponent may have you put that card into your graveyard. If a player does, this creature deals damage to that player equal to that card's mana value. Otherwise, put that card into your hand.

Suspended Sentence

Destroy target creature an opponent controls. That player loses 3 life. Exile Suspended Sentence with three time counters on it.
Suspend 3—{1}{B} (Rather than cast this card from your hand, you may pay {1}{B} and exile it with three 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.)