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.

Sunken Hollow

({T}: Add {U} or {B}.)
Sunken Hollow enters tapped unless you control two or more basic lands.

Lizard Blades

Double strike
Equipped creature has double strike.
Reconfigure {2} ({2}: Attach to target creature you control; or unattach from a creature. Reconfigure only as a sorcery. While attached, this isn't a creature.)

Conqueror's Flail

Equipped creature gets +1/+1 for each color among permanents you control.
As long as Conqueror's Flail is attached to a creature, your opponents can't cast spells during your turn.
Equip {2}

Mithril Coat

Flash
Indestructible
When Mithril Coat enters, attach it to target legendary creature you control.
Equipped creature has indestructible.
Equip {3}

Blackblade Reforged

Equipped creature gets +1/+1 for each land you control.
Equip legendary creature {3}
Equip {7}

Doom Blade

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.

Blood Crypt

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

Path of Ancestry

Path of Ancestry enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Luxury Suite

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

Barrin's Codex

At the beginning of your upkeep, you may put a page counter on Barrin's Codex.
{4}, {T}, Sacrifice Barrin's Codex: Draw X cards, where X is the number of page counters on Barrin's Codex.

Thought Vessel

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

Rakdos Signet

Dragonskull Summit

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

Izzet Signet

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Fellwar Stone

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

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.

Swamp

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.)

Drowned Catacomb

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

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Exotic Orchard

Netherese Puzzle-Ward

Focus Beam — At the beginning of your upkeep, roll a d4. Scry X, where X is the result.
Perfect Illumination — Whenever you roll a die's highest natural result, draw a card.

Rhystic Study

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

Smoldering Marsh

({T}: Add {B} or {R}.)
Smoldering Marsh enters tapped unless you control two or more basic lands.

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.

Gravestorm

At the beginning of your upkeep, target opponent may exile a card from their graveyard. If that player doesn't, you may draw a card.

Lightning Greaves

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

Morphic Pool

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

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.

Island

Vandalblast

Destroy target artifact you don't control.
Overload {4}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

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.)

Court of Ire

When Court of Ire enters, you become the monarch.
At the beginning of your upkeep, Court of Ire deals 2 damage to any target. If you're the monarch, it deals 7 damage instead.

Creeping Bloodsucker

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

Counterspell

Shrine of Burning Rage

At the beginning of your upkeep and 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.

Dark Ritual

Watery Grave

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

Court of Cunning

When Court of Cunning 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.)

Fiery Emancipation

If a source you control would deal damage to a permanent or player, it deals triple that damage to that permanent or player instead.

Talisman of Indulgence

{T}: Add {C}.
{T}: Add {B} or {R}. Talisman of Indulgence deals 1 damage to you.

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.

Dimir Signet

Feed the Swarm

Destroy target creature or enchantment an opponent controls. You lose life equal to that permanent's mana value.

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.

Shrine of Loyal Legions

At the beginning of your upkeep and whenever you cast a white spell, put a charge counter on Shrine of Loyal Legions.
{3}, {T}, Sacrifice Shrine of Loyal Legions: Create a 1/1 colorless Phyrexian Myr artifact creature token for each charge counter on Shrine of Loyal Legions.

Talisman of Dominance

{T}: Add {C}.
{T}: Add {U} or {B}. Talisman of Dominance deals 1 damage to you.

Bitterblossom

At the beginning of your upkeep, you lose 1 life and create a 1/1 black Faerie Rogue creature token with flying.

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."

Steam Vents

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

Shrine of Boundless Growth

At the beginning of your upkeep and whenever you cast a green spell, put a charge counter on Shrine of Boundless Growth.
{T}, Sacrifice Shrine of Boundless Growth: Add {C} for each charge counter on Shrine of Boundless Growth.

Court of Locthwain

When Court of Locthwain enters, you become the monarch.
At the beginning of your upkeep, exile the top card of target opponent's library. You may play that card for as long as it remains exiled, and mana of any type can be spent to cast it. If you're the monarch, until end of turn, you may cast a spell from among cards exiled with Court of Locthwain without paying its mana cost.

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.

Training Center

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

Rogue's Passage

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

Trailblazer's Boots

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

Negate

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.

Court of Ambition

When Court of Ambition 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.

Court of Embereth

When Court of Embereth enters, you become the monarch.
At the beginning of your upkeep, create a 3/1 red Knight creature token. Then if you're the monarch, Court of Embereth deals X damage to each opponent, where X is the number of creatures you control.

Reliquary Tower

Chronozoa

Flying
Vanishing 3 (This creature enters with three time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
When Chronozoa dies, if it had no time counters on it, create two tokens that are copies of it.

Blood Tyrant

Flying, trample
At the beginning of your upkeep, each player loses 1 life. Put a +1/+1 counter on Blood Tyrant for each 1 life lost this way.
Whenever a player loses the game, put five +1/+1 counters on Blood Tyrant.

Sol Ring

Silent Arbiter

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

Mountain

Bloodletter of Aclazotz

Flying
If an opponent would lose life during your turn, they lose twice that much life instead. (Damage causes loss of life.)

As Foretold

At the beginning of your upkeep, put a time counter on As Foretold.
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 As Foretold.

Sulfur Falls

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

Rapid Hybridization

Destroy target creature. It can't be regenerated. That creature's controller creates a 3/3 green Frog Lizard creature token.

Arcane Signet

Whispersilk Cloak

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

Terminate

Destroy target creature. It can't be regenerated.

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.

Roaming Throne

Ward {2}
As Roaming Throne enters, choose a creature type.
Roaming Throne is the chosen type in addition to its other types.
If a triggered ability of another creature you control of the chosen type triggers, it triggers an additional time.

Minas Morgul, Dark Fortress

Minas Morgul, Dark Fortress enters tapped.
{T}: Add {B}.
{3}{B}, {T}: Put a shadow counter on target creature. For as long as that creature has a shadow counter on it, it's a Wraith in addition to its other types. (A creature with shadow can block or be blocked by only creatures with shadow.)

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.)

Talisman of Creativity

{T}: Add {C}.
{T}: Add {U} or {R}. Talisman of Creativity deals 1 damage to you.

Court of Vantress

When Court of Vantress enters, you become the monarch.
At the beginning of your upkeep, choose up to one other target enchantment or artifact. If you're the monarch, you may create a token that's a copy of it. If you're not the monarch, you may have Court of Vantress become a copy of it, except it has this ability.

Braids, Conjurer Adept

At the beginning of each player's upkeep, that player may put an artifact, creature, or land card from their hand onto the battlefield.

Shore Up

Target creature you control gets +1/+1 and gains hexproof until end of turn. Untap it. (It can't be the target of spells or abilities your opponents control.)