Arcane Signet

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

Teferi's Protection

Until your next turn, your life total can't change and you gain protection from everything. All permanents you control phase out. (While they're phased out, they're treated as though they don't exist. They phase in before you untap during your untap step.)
Exile Teferi's Protection.

Propaganda

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Absolute Law

Precinct Captain

First strike
Whenever Precinct Captain deals combat damage to a player, create a 1/1 white Soldier creature token.

Enlightened Tutor

Search your library for an artifact or enchantment card, reveal it, then shuffle and put that card on top.

Azorius Arrester

When Azorius Arrester enters, detain target creature an opponent controls. (Until your next turn, that creature can't attack or block and its activated abilities can't be activated.)

Lawmage's Binding

Flash
Enchant creature
Enchanted creature can't attack or block, and its activated abilities can't be activated.

Arrester's Admonition

Return target creature to its owner's hand.
Addendum — If you cast this spell during your main phase, draw a card.

Ghostly Prison

Flawless Maneuver

If you control a commander, you may cast this spell without paying its mana cost.
Creatures you control gain indestructible until end of turn.

Gideon, Champion of Justice

+1: Put a loyalty counter on Gideon, Champion of Justice for each creature target opponent controls.
0: Until end of turn, Gideon, Champion of Justice becomes a Human Soldier creature with power and toughness each equal to the number of loyalty counters on him and gains indestructible. He's still a planeswalker. Prevent all damage that would be dealt to him this turn.
−15: Exile all other permanents.

Archon of Justice

Flying
When Archon of Justice dies, exile target permanent.

Sol Ring

Lyev Decree

Detain up to two target creatures your opponents control. (Until your next turn, those creatures can't attack or block and their activated abilities can't be activated.)

Entrapment Maneuver

Target player sacrifices an attacking creature. You create X 1/1 white Soldier creature tokens, where X is that creature's toughness.

Arrest

Enchant creature
Enchanted creature can't attack or block, and its activated abilities can't be activated.

Checkpoint Officer

Armed with Proof

When Armed with Proof enters, investigate twice. (To investigate, create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")
Clues you control are Equipment in addition to their other types and have "Equipped creature gets +2/+0" and equip {2}.

Thopter Arrest

When Thopter Arrest enters, exile target artifact or creature an opponent controls until Thopter Arrest leaves the battlefield.

Gideon's Lawkeeper

The Mightstone and Weakstone

When The Mightstone and Weakstone enters, choose one —
• Draw two cards.
• Target creature gets -5/-5 until end of turn.
{T}: Add {C}{C}. This mana can't be spent to cast nonartifact spells.
(Melds with Urza, Lord Protector.)

Urza, Lord Protector

Artifact, instant, and sorcery spells you cast cost {1} less to cast.
{7}: If you both own and control Urza, Lord Protector and an artifact named The Mightstone and Weakstone, exile them, then meld them into Urza, Planeswalker. Activate only as a sorcery.

Lavinia of the Tenth

Protection from red
When Lavinia of the Tenth enters, detain each nonland permanent your opponents control with mana value 4 or less. (Until your next turn, those permanents can't attack or block and their activated abilities can't be activated.)

Grand Abolisher

During your turn, your opponents can't cast spells or activate abilities of artifacts, creatures, or enchantments.

Dovin, Architect of Law

+1: You gain 2 life and draw a card.
−1: Tap target creature. It doesn't untap during its controller's next untap step.
−9: Tap all permanents target opponent controls. That player skips their next untap step.

Intercessor's Arrest

Enchant permanent
Enchanted permanent can't attack, block, or crew Vehicles. Its activated abilities can't be activated unless they're mana abilities.

Silence

Your opponents can't cast spells this turn.

Citizen's Arrest

When Citizen's Arrest enters, exile target creature or planeswalker an opponent controls until Citizen's Arrest leaves the battlefield.

Murder Investigation

Enchant creature you control
When enchanted creature dies, create X 1/1 white Soldier creature tokens, where X is its power.

Law-Rune Enforcer

{1}, {T}: Tap target creature with mana value 2 or greater.

Blind Obedience

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)
Artifacts and creatures your opponents control enter tapped.

Detainment Spell

Enchant creature
Enchanted creature's activated abilities can't be activated.
{1}{W}: Attach Detainment Spell to target creature.

Akroan Jailer

Isolation Cell

Whenever an opponent casts a creature spell, that player loses 2 life unless they pay {2}.

Sword of Truth and Justice

Equipped creature gets +2/+2 and has protection from white and from blue.
Whenever equipped creature deals combat damage to a player, put a +1/+1 counter on a creature you control, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)
Equip {2}

Azorius Signet

Mind Stone

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

Sphere of Safety

Creatures can't attack you or planeswalkers you control unless their controller pays {X} for each of those creatures, where X is the number of enchantments you control.

Elite Arrester

Counterspell

Detention Sphere

When Detention Sphere enters, you may exile target nonland permanent not named Detention Sphere and all other permanents with the same name as that permanent.
When Detention Sphere leaves the battlefield, return the exiled cards to the battlefield under their owner's control.

Ordered Migration

Domain — Create a 1/1 blue Bird creature token with flying for each basic land type among lands you control.

Curious Inquiry

Enchant creature
Enchanted creature gets +1/+1 and has "Whenever this creature deals combat damage to a player, investigate." (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Command Tower

Press for Answers

Tap target creature. It doesn't untap during its controller's next untap step.
Investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Disallow

Counter target spell, activated ability, or triggered ability. (Mana abilities can't be targeted.)

Grand Arbiter Augustin IV

White spells you cast cost {1} less to cast.
Blue spells you cast cost {1} less to cast.
Spells your opponents cast cost {1} more to cast.

Hixus, Prison Warden

Flash (You may cast this spell any time you could cast an instant.)
Whenever a creature deals combat damage to you, if Hixus, Prison Warden entered this turn, exile that creature until Hixus leaves the battlefield. (That creature returns under its owner's control.)

Supreme Verdict

This spell can't be countered.
Destroy all creatures.

Rule of Law

Each player can't cast more than one spell each turn.

Soulless Jailer

Permanent cards in graveyards can't enter the battlefield.
Players can't cast noncreature spells from graveyards or exile.

Dispense Justice

Target player sacrifices an attacking creature.
Metalcraft — That player sacrifices two attacking creatures instead if you control three or more artifacts.

Land Tax

At the beginning of your upkeep, if an opponent controls more lands than you, you may search your library for up to three basic land cards, reveal them, put them into your hand, then shuffle.

Plains

Soul Warden

Whenever another creature enters, you gain 1 life.

Martial Law

At the beginning of your upkeep, detain target creature an opponent controls. (Until your next turn, that creature can't attack or block and its activated abilities can't be activated.)

Dismiss

Island

Deafening Silence

Each player can't cast more than one noncreature spell each turn.

Azorius Justiciar

When Azorius Justiciar enters, detain up to two target creatures your opponents control. (Until your next turn, those creatures can't attack or block and their activated abilities can't be activated.)

Deduce

Draw a card. Investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Azor, the Lawbringer

Flying
When Azor, the Lawbringer enters, each opponent can't cast instant or sorcery spells during that player's next turn.
Whenever Azor attacks, you may pay {X}{W}{U}{U}. If you do, you gain X life and draw X cards.

Sun Titan

Vigilance
Whenever Sun Titan enters or attacks, you may return target permanent card with mana value 3 or less from your graveyard to the battlefield.

Isperia, Supreme Judge

Flying
Whenever a creature attacks you or a planeswalker you control, you may draw a card.