Stalwart Shield-Bearers

Defender
Other creatures you control with defender get +0/+2.

Mnemonic Wall

Defender
When Mnemonic Wall enters, you may return target instant or sorcery card from your graveyard to your hand.

Weathered Sentinels

Defender, vigilance, reach, trample
Weathered Sentinels can attack players who attacked you during their last turn as though it didn't have defender.
Whenever Weathered Sentinels attacks, it gets +3/+3 and gains indestructible until end of turn.

High Alert

Each creature you control assigns combat damage equal to its toughness rather than its power.
Creatures you control can attack as though they didn't have defender.
{2}{W}{U}: Untap target creature.

Serra's Blessing

Creatures you control have vigilance. (Attacking doesn't cause them to tap.)

Sokrates, Athenian Teacher

Defender
Sokrates, Athenian Teacher has hexproof as long as it's untapped.
Sokratic Dialogue — {T}: Until end of turn, target creature gains "If this creature would deal combat damage to a player, prevent that damage. This creature's controller and that player each draw half that many cards, rounded down."

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Decanter of Endless Water

You have no maximum hand size.
{T}: Add one mana of any color.

Suspicious Bookcase

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

Wall of Tears

Defender (This creature can't attack.)
Whenever Wall of Tears blocks a creature, return that creature to its owner's hand at end of combat.

Generous Gift

Destroy target permanent. Its controller creates a 3/3 green Elephant creature token.

Vine Trellis

Defender (This creature can't attack.)
{T}: Add {G}.

Island

Rammas Echor, Ancient Shield

Whenever you cast your second spell each turn, draw a card, then create a 0/3 white Wall creature token with defender.
At the beginning of combat on your turn, creatures you control with defender gain exalted until end of turn. (Whenever a creature you control attacks alone, it gets +1/+1 until end of turn for each instance of exalted among permanents you control.)

Beast Within

Destroy target permanent. Its controller creates a 3/3 green Beast creature token.

Adarkar Wastes

{T}: Add {C}.
{T}: Add {W} or {U}. Adarkar Wastes deals 1 damage to you.

Spidersilk Armor

Creatures you control get +0/+1 and have reach. (They can block creatures with flying.)

Hinterland Harbor

Hinterland Harbor enters tapped unless you control a Forest or an Island.
{T}: Add {G} or {U}.

Plains

Stoneskin

Flash
Enchant creature
Enchanted creature gets +0/+10.

Wall of Blossoms

Defender
When Wall of Blossoms enters, draw a card.

Sylvan Caryatid

Defender, hexproof
{T}: Add one mana of any color.

Three Visits

Search your library for a Forest card, put it onto the battlefield, then shuffle.

Brushland

{T}: Add {C}.
{T}: Add {G} or {W}. Brushland deals 1 damage to you.

Wingmantle Chaplain

Defender
When Wingmantle Chaplain enters, create a 1/1 white Bird creature token with flying for each creature with defender you control.
Whenever another creature you control with defender enters, create a 1/1 white Bird creature token with flying.

Nature's Lore

Search your library for a Forest card, put that card onto the battlefield, then shuffle.

Crashing Drawbridge

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

Wall of Junk

Defender (This creature can't attack.)
When Wall of Junk blocks, return it to its owner's hand at end of combat. (Return it only if it's on the battlefield.)

Arcane Signet

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

Axebane Guardian

Defender
{T}: Add X mana in any combination of colors, where X is the number of creatures you control with defender.

Reliquary Tower

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

Thought Vessel

Seaside Citadel

Seaside Citadel enters tapped.
{T}: Add {G}, {W}, or {U}.

Overgrown Battlement

Defender
{T}: Add {G} for each creature you control with defender.

The Pride of Hull Clade

This spell costs {X} less to cast, where X is the total toughness of creatures you control.
Defender
{2}{U}{U}: Until end of turn, target creature you control gets +1/+0, gains "Whenever this creature deals combat damage to a player, draw cards equal to its toughness," and can attack as though it didn't have defender.

Shield-Wall Sentinel

Defender
When Shield-Wall Sentinel enters, you may search your library for a creature card with defender, reveal it, put it into your hand, then shuffle.

Dawn

Aftermath (Cast this spell only from your graveyard. Then exile it.)
Return all creature cards with power 2 or less from your graveyard to your hand.

Dusk

Destroy all creatures with power 3 or greater.

Dusk // Dawn

Always Watching

Nontoken creatures you control get +1/+1 and have vigilance.

Brave the Sands

Creatures you control have vigilance.
Each creature you control can block an additional creature each combat.

Angelic Chorus

Whenever a creature you control enters, you gain life equal to its toughness.

Rogue's Passage

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

Access Tunnel

{T}: Add {C}.
{3}, {T}: Target creature with power 3 or less can't be blocked this turn.

Assault Formation

Each creature you control assigns combat damage equal to its toughness rather than its power.
{G}: Target creature with defender can attack this turn as though it didn't have defender.
{2}{G}: Creatures you control get +0/+1 until end of turn.

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Cultivate

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Jeskai Barricade

Flash (You may cast this spell any time you could cast an instant.)
Defender
When Jeskai Barricade enters, you may return another target creature you control to its owner's hand.

Wall of Denial

Defender, flying
Shroud (This creature can't be the target of spells or abilities.)

Mirror Shield

Equipped creature gets +0/+2 and has hexproof and "Whenever a creature with deathtouch blocks or becomes blocked by this creature, destroy that creature."
Equip {2} ({2}: Attach to target creature you control. Equip 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.)

Tetsuko Umezawa, Fugitive

Creatures you control with power or toughness 1 or less can't be blocked.

Wall of Frost

Defender
Whenever Wall of Frost blocks a creature, that creature doesn't untap during its controller's next untap step.

Sunscape Familiar

Defender (This creature can't attack.)
Green spells and blue spells you cast cost {1} less to cast.

Counterspell

Fog Bank

Defender (This creature can't attack.)
Flying
Prevent all combat damage that would be dealt to and dealt by this creature.

Fellwar Stone

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

Yavimaya Coast

{T}: Add {C}.
{T}: Add {G} or {U}. Yavimaya Coast deals 1 damage to you.

Exotic Orchard

Arcades, the Strategist

Flying, vigilance
Whenever a creature you control with defender enters, draw a card.
Each creature you control with defender assigns combat damage equal to its toughness rather than its power and can attack as though it didn't have defender.

Farseek

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Amaranthine Wall

Defender
{2}: Amaranthine Wall gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Sunpetal Grove

Sunpetal Grove enters tapped unless you control a Forest or a Plains.
{T}: Add {G} or {W}.

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Prairie Stream

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

Hover Barrier

Wall of Tanglecord

Defender
{G}: Wall of Tanglecord gains reach until end of turn. (It can block creatures with flying.)

Evolving Wilds

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Slaughter the Strong

Each player chooses any number of creatures they control with total power 4 or less, then sacrifices all other creatures they control.

Walking Bulwark

Defender
{2}: Until end of turn, target creature with defender gains haste, can attack as though it didn't have defender, and assigns combat damage equal to its toughness rather than its power. Activate only as a sorcery.

Command Tower

Glacial Fortress

Glacial Fortress enters tapped unless you control a Plains or an Island.
{T}: Add {W} or {U}.

Forest

Wall of Omens

Defender
When Wall of Omens enters, draw a card.

Sight of the Scalelords

At the beginning of combat on your turn, creatures you control with toughness 4 or greater get +2/+2 and gain vigilance until end of turn.

The Battle of Bywater

Destroy all creatures with power 3 or greater. Then create a Food token for each creature you control. (It's an artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life.")

Perimeter Captain

Defender
Whenever a creature you control with defender blocks, you may gain 2 life.

Wall of Runes

Defender (This creature can't attack.)
When Wall of Runes enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Unbreakable Formation

Creatures you control gain indestructible until end of turn.
Addendum — If you cast this spell during your main phase, put a +1/+1 counter on each of those creatures and they gain vigilance until end of turn.

Sol Ring

Stroke of Midnight

Destroy target nonland permanent. Its controller creates a 1/1 white Human creature token.

Fell the Mighty

Destroy all creatures with power greater than target creature's power.

Wall of Stolen Identity

You may have Wall of Stolen Identity enter as a copy of any creature on the battlefield, except it's a Wall in addition to its other types and has defender. When you do, tap the copied creature and it doesn't untap during its controller's untap step for as long as you control Wall of Stolen Identity.

Canopy Vista

({T}: Add {G} or {W}.)
Canopy Vista enters tapped unless you control two or more basic lands.