Plains

Psychic Impetus

Enchant creature
Enchanted creature gets +2/+2 and is goaded. (It attacks each combat if able and attacks a player other than you if able.)
Whenever enchanted creature attacks, you scry 2.

Staggering Insight

Enchant creature
Enchanted creature gets +1/+1 and has lifelink and "Whenever this creature deals combat damage to a player, draw a card."

Rogue's Passage

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

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.)

Indestructibility

Enchant permanent
Enchanted permanent has indestructible. (Effects that say "destroy" don't destroy that permanent. A creature with indestructible can't be destroyed by damage.)

Cut Your Losses

Casualty 2 (As you cast this spell, you may sacrifice a creature with power 2 or greater. When you do, copy this spell and you may choose a new target for the copy.)
Target player mills half their library, rounded down.

Path of Ancestry

Path of Ancestry enters the battlefield 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.)

Mantle of the Ancients

Enchant creature you control
When Mantle of the Ancients enters the battlefield, return any number of target Aura and/or Equipment cards from your graveyard to the battlefield attached to enchanted creature.
Enchanted creature gets +1/+1 for each Aura and Equipment attached to it.

Irrigated Farmland

({T}: Add {W} or {U}.)
Irrigated Farmland enters the battlefield tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

Steel of the Godhead

Enchant creature
As long as enchanted creature is white, it gets +1/+1 and has lifelink. (Damage dealt by the creature also causes its controller to gain that much life.)
As long as enchanted creature is blue, it gets +1/+1 and can't be blocked.

Sol Ring

Crashing Drawbridge

Defender
{T}: Creatures you control gain haste until end of turn.

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 of your library.)

Auramancer's Guise

Enchant creature
Enchanted creature gets +2/+2 for each Aura attached to it and has vigilance.

Gold-Forged Thopteryx

Flying, lifelink
Each legendary permanent you control has ward {2}. (Whenever it becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)

Traumatize

Target player mills half their library, rounded down.

Worn Powerstone

Worn Powerstone enters the battlefield tapped.
{T}: Add {C}{C}.

Mirror-Mad Phantasm

Flying
{1}{U}: Mirror-Mad Phantasm's owner shuffles it into their library. If that player does, they reveal cards from the top of that library until a card named Mirror-Mad Phantasm is revealed. The player puts that card onto the battlefield and all other cards revealed this way into their graveyard.

Empyrial Armor

Enchant creature
Enchanted creature gets +1/+1 for each card in your hand.

Counterspell

Battle Mastery

Enchant creature
Enchanted creature has double strike. (It deals both first-strike and regular combat damage.)

Sage's Reverie

Enchant creature
When Sage's Reverie enters the battlefield, draw a card for each Aura you control that's attached to a creature.
Enchanted creature gets +1/+1 for each Aura you control that's attached to a creature.

Shielded by Faith

Enchant creature
Enchanted creature has indestructible.
Whenever a creature enters the battlefield, you may attach Shielded by Faith to that creature.

Open the Armory

Search your library for an Aura or Equipment card, reveal it, put it into your hand, then shuffle.

Curiosity

Enchant creature
Whenever enchanted creature deals damage to an opponent, you may draw a card.

Loyal Warhound

Vigilance
When Loyal Warhound enters the battlefield, if an opponent controls more lands than you, search your library for a basic Plains card, put it onto the battlefield tapped, then shuffle.

Blacksmith's Skill

Target permanent gains hexproof and indestructible until end of turn. If it's an artifact creature, it gets +2/+2 until end of turn.

Heliod's Pilgrim

When Heliod's Pilgrim enters the battlefield, you may search your library for an Aura card, reveal it, put it into your hand, then shuffle.

Sovereigns of Lost Alara

Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)
Whenever a creature you control attacks alone, you may search your library for an Aura card that could enchant that creature, put it onto the battlefield attached to that creature, then shuffle.

Swiftfoot Boots

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

Pippin, Guard of the Citadel

Vigilance, ward {1}
{T}: Another target creature you control gains protection from the card type of your choice until end of turn. (It can't be blocked, targeted, dealt damage, enchanted, or equipped by anything of that type.)

Diplomatic Immunity

Enchant creature
Shroud (A permanent with shroud can't be the target of spells or abilities.)
Enchanted creature has shroud.

Temple of Enlightenment

Temple of Enlightenment enters the battlefield tapped.
When Temple of Enlightenment enters the battlefield, scry 1.
{T}: Add {W} or {U}.

Corrupted Conscience

Enchant creature
You control enchanted creature.
Enchanted creature has infect. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Chains of Custody

Enchant creature you control
When Chains of Custody enters the battlefield, exile target nonland permanent an opponent controls until Chains of Custody leaves the battlefield.
Enchanted creature has ward {2}. (Whenever it becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)

Arcane Signet

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

Azorius Signet

Hyena Umbra

Enchant creature
Enchanted creature gets +1/+1 and has first strike.
Umbra armor (If enchanted creature would be destroyed, instead remove all damage from it and destroy this Aura.)

Karametra's Blessing

Target creature gets +2/+2 until end of turn. If it's an enchanted creature or enchantment creature, it also gains hexproof and indestructible until end of turn. (It can't be the target of spells or abilities your opponents control. Damage and effects that say "destroy" don't destroy it.)

Thirst for Meaning

Draw three cards. Then discard two cards unless you discard an enchantment card.

Island

Archon of Sun's Grace

Flying, lifelink
Pegasus creatures you control have lifelink.
Constellation — Whenever an enchantment enters the battlefield under your control, create a 2/2 white Pegasus creature token with flying.

Faith Unbroken

Enchant creature you control
When Faith Unbroken enters the battlefield, exile target creature an opponent controls until Faith Unbroken leaves the battlefield.
Enchanted creature gets +2/+2.

All That Glitters

Enchant creature
Enchanted creature gets +1/+1 for each artifact and/or enchantment you control.

Commander's Sphere

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

Loran's Escape

Target artifact or creature gains hexproof and indestructible until end of turn. Scry 1.

Hour of Revelation

This spell costs {3} less to cast if there are ten or more nonland permanents on the battlefield.
Destroy all nonland permanents.

Righteous Authority

Enchant creature
Enchanted creature gets +1/+1 for each card in its controller's hand.
At the beginning of the draw step of enchanted creature's controller, that player draws an additional card.

Thran Dynamo

Port Town

As Port Town enters the battlefield, you may reveal a Plains or Island card from your hand. If you don't, Port Town enters the battlefield tapped.
{T}: Add {W} or {U}.

Command Tower

Glacial Floodplain

({T}: Add {W} or {U}.)
Glacial Floodplain enters the battlefield tapped.

Esior, Wardwing Familiar

Flying
Spells your opponents cast that target one or more commanders you control cost {3} more to cast.
Partner (You can have two commanders if both have partner.)

Unquestioned Authority

Enchant creature
When Unquestioned Authority enters the battlefield, draw a card.
Enchanted creature has protection from creatures.

Skycloud Expanse

Faithful Mending

You gain 2 life, draw two cards, then discard two cards.
Flashback {1}{W}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Fellwar Stone

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

Sigil of the Empty Throne

Whenever you cast an enchantment spell, create a 4/4 white Angel creature token with flying.

Vanishing

Enchant creature
{U}{U}: Enchanted creature phases out. (While it's phased out, it's treated as though it doesn't exist. It phases in before its controller untaps during their next untap step.)

Ephara, Ever-Sheltering

Ephara, Ever-Sheltering has lifelink and indestructible as long as you control at least three other enchantments.
Whenever another enchantment enters the battlefield under your control, draw a card.

Invasion of Theros

(As a Siege enters, choose an opponent to protect it. You and others can attack it. When it's defeated, exile it, then cast it transformed.)
When Invasion of Theros enters the battlefield, search your library for an Aura, God, or Demigod card, reveal it, put it into your hand, then shuffle.

Invasion of Theros // Ephara, Ever-Sheltering

Prairie Stream

({T}: Add {W} or {U}.)
Prairie Stream enters the battlefield tapped unless you control two or more basic lands.

Ethereal Armor

Enchant creature
Enchanted creature gets +1/+1 for each enchantment you control and has first strike.

Combat Research

Enchant creature
Enchanted creature has "Whenever this creature deals combat damage to a player, draw a card."
As long as enchanted creature is legendary, it gets +1/+1 and has ward {1}. (Whenever enchanted creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {1}.)

Eel Umbra

Flash (You may cast this spell any time you could cast an instant.)
Enchant creature
Enchanted creature gets +1/+1.
Umbra armor (If enchanted creature would be destroyed, instead remove all damage from it and destroy this Aura.)

Knight of the White Orchid

First strike
When Knight of the White Orchid enters the battlefield, if an opponent controls more lands than you, you may search your library for a Plains card, put it onto the battlefield, then shuffle.

Azorius Chancery

Azorius Chancery enters the battlefield tapped.
When Azorius Chancery enters the battlefield, return a land you control to its owner's hand.
{T}: Add {W}{U}.

Octopus Umbra

Enchant creature
Enchanted creature has base power and toughness 8/8 and has "Whenever this creature attacks, you may tap target creature with power 8 or less."
Umbra armor (If enchanted creature would be destroyed, instead remove all damage from it and destroy this Aura.)

Minimus Containment

Enchant nonland permanent
Enchanted permanent is a Treasure artifact with "{T}, Sacrifice this artifact: Add one mana of any color," and it loses all other abilities. (If it was a creature, it's no longer a creature.)

Frantic Search

Draw two cards, then discard two cards. Untap up to three lands.

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.

Sage of Mysteries

Constellation — Whenever an enchantment enters the battlefield under your control, target player mills two cards.

Bruna, Light of Alabaster

Flying, vigilance
Whenever Bruna, Light of Alabaster attacks or blocks, you may attach to it any number of Auras on the battlefield and you may put onto the battlefield attached to it any number of Aura cards that could enchant it from your graveyard and/or hand.

Face of Divinity

Enchant creature
Enchanted creature gets +2/+2.
As long as another Aura is attached to enchanted creature, it has first strike and lifelink.