Have

Command Tower

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

High Synergy

Wall of Frost

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

Maybe?

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 token: You gain 3 life.")

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.

Exotic Orchard

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

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.

Swords to Plowshares

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

Sol Ring

Simic Growth Chamber

This land enters tapped.
When this land enters, return a land you control to its owner's hand.
{T}: Add {G}{U}.

In Dino fight

Panharmonicon

If an artifact or creature entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Bar the Door

Creatures you control get +0/+4 until end of turn.

Towering Titan

This creature enters with X +1/+1 counters on it, where X is the total toughness of other creatures you control.
Sacrifice a creature with defender: All creatures gain trample 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.

Reliquary Tower

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

Proxy it?

Plagon, Lord of the Beach

When Plagon enters, draw a card for each creature you control with toughness greater than its power.
{W/U}: Target creature you control assigns combat damage equal to its toughness rather than its power this turn.

Wall of Glare

Defender (This creature can't attack.)
This creature can block any number of creatures.

Dovin's Veto

This spell can't be countered.
Counter target noncreature spell.

Akroma's Will

Choose one. If you control a commander as you cast this spell, you may choose both instead.
• Creatures you control gain flying, vigilance, and double strike until end of turn.
• Creatures you control gain lifelink, indestructible, and protection from each color until end of turn.

Drift of Phantasms

Defender (This creature can't attack.)
Flying
Transmute {1}{U}{U} ({1}{U}{U}, Discard this card: Search your library for a card with the same mana value as this card, reveal it, put it into your hand, then shuffle. Transmute only as a sorcery.)

Questionable

Generous Gift

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

Rampant Growth

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

Aegis of the Heavens

Target creature gets +1/+7 until end of turn.

Shield-Wall Sentinel

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

Weathered Sentinels

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

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.

Meekstone

Creatures with power 3 or greater don't untap during their controllers' untap steps.

Angel's Trumpet

All creatures have vigilance.
At the beginning of each player's end step, tap all untapped creatures that player controls that didn't attack this turn. This artifact deals damage to the player equal to the number of creatures tapped this way.

Arcane Signet

Spara's Headquarters

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

Riptide Turtle

Fell the Mighty

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

Plains

Guardian Project

Whenever a nontoken creature you control enters, if it doesn't have the same name as another creature you control or a creature card in your graveyard, draw a card.

Tocasia's Welcome

Whenever one or more creatures you control with mana value 3 or less enter, draw a card. This ability triggers only once each turn.

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.

Wall of Blossoms

Defender
When this creature enters, draw a card.

Wall of Runes

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

Azorius Chancery

This land enters tapped.
When this land enters, return a land you control to its owner's hand.
{T}: Add {W}{U}.

Wall of Roots

Defender
Put a -0/-1 counter on this creature: Add {G}. Activate only once each turn.

Shield Sphere

Defender
Whenever this creature blocks, put a -0/-1 counter on it.

Sylvan Caryatid

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

Sidar Kondo of Jamuraa

Flanking (Whenever a creature without flanking blocks this creature, the blocking creature gets -1/-1 until end of turn.)
Creatures your opponents control without flying or reach can't block creatures with power 2 or less.
Partner (You can have two commanders if both have partner.)

Eerie Interlude

Exile any number of target creatures you control. Return those cards to the battlefield under their owner's control at the beginning of the next end step.

Bedrock Tortoise

During your turn, creatures you control have hexproof.
Each creature you control with toughness greater than its power assigns combat damage equal to its toughness rather than its power.

Suspicious Bookcase

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

Teyo, the Shieldmage

You have hexproof. (You can't be the target of spells or abilities your opponents control.)
−2: Create a 0/3 white Wall creature token with defender.

Wingmantle Chaplain

Defender
When this creature 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.

Axebane Guardian

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

Wall of Junk

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

Animate Wall

Enchant Wall
Enchanted Wall can attack as though it didn't have defender.

Aspect of Mongoose

Enchant creature
Enchanted creature has shroud. (It can't be the target of spells or abilities.)
When this Aura is put into a graveyard from the battlefield, return it to its owner's hand.

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

Stoneskin

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

Heroic Intervention

Permanents you control gain hexproof and indestructible until end of turn.

Wall of Stolen Identity

You may have this creature 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 this creature.

Decent

Soulsworn Jury

Defender (This creature can't attack.)
{1}{U}, Sacrifice this creature: Counter target creature spell.

Wall of Denial

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

Wall of Omens

Wakestone Gargoyle

Defender, flying
{1}{W}: Creatures you control with defender can attack this turn as though they didn't have defender.

Tree of Redemption

Defender
{T}: Exchange your life total with this creature's toughness.

Overgrown Battlement

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

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.

Tranquil Landscape

{T}: Add {C}.
{T}, Sacrifice this land: Search your library for a basic Forest, Plains, or Island card, put it onto the battlefield tapped, then shuffle.
Cycling {G}{W}{U} ({G}{W}{U}, Discard this card: Draw a card.)

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.)

Hover Barrier

Gaea's Blessing

Target player shuffles up to three target cards from their graveyard into their library.
Draw a card.
When this card is put into your graveyard from your library, shuffle your graveyard into your library.

Prairie Stream

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

Wall of Tears

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

Rune-Sealed Wall

Defender
{T}: Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Crashing Drawbridge

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

Ghostway

Exile each creature you control. Return those cards to the battlefield under their owner's control at the beginning of the next end step.

Hinterland Harbor

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

Flumph

Defender, flying
Whenever this creature is dealt damage, you and target opponent each draw a card.

Charix, the Raging Isle

Spells your opponents cast that target Charix cost {2} more to cast.
{3}: Charix gets +X/-X until end of turn, where X is the number of Islands you control.

Selesnya Signet

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.

Wall of Mulch

Defender (This creature can't attack.)
{G}, Sacrifice a Wall: Draw a card.

Teferi's Ageless Insight

If you would draw a card except the first one you draw in each of your draw steps, draw two cards instead.

Counterspell

Brave the Sands

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

Canopy Vista

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

Huatli, the Sun's Heart

Each creature you control assigns combat damage equal to its toughness rather than its power.
−3: You gain life equal to the greatest toughness among creatures you control.

Wave of Reckoning

Each creature deals damage to itself equal to its power.

Tower Defense

Creatures you control get +0/+5 and gain reach until end of turn.

Tetsuko Umezawa, Fugitive

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

Seaside Citadel

This land enters tapped.
{T}: Add {G}, {W}, or {U}.

Primal Rage

Creatures you control have trample. (A creature with trample can deal excess combat damage to the player or planeswalker it's attacking.)

Solidarity

Creatures you control get +0/+5 until end of turn.

Angelic Chorus

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

Sunpetal Grove

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

Perimeter Captain

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

Traproot Kami

Defender; reach (This creature can block creatures with flying.)
Traproot Kami's toughness is equal to the number of Forests on the battlefield.

Rogue's Passage

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

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.

Beast Within

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

Crystal Barricade

Defender (This creature can't attack.)
You have hexproof. (You can't be the target of spells or abilities your opponents control.)
Prevent all noncombat damage that would be dealt to other creatures you control.

Worldly Tutor

Search your library for a creature card, reveal it, then shuffle and put the card on top.

Carven Caryatid

Defender (This creature can't attack.)
When this creature enters, draw a card.

Vine Trellis

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

Expel the Interlopers

Choose a number between 0 and 10. Destroy all creatures with power greater than or equal to the chosen number.