Fortified Area

Wall creatures you control get +1/+0 and have banding. (Any creatures with banding, and up to one without, can attack in a band. Bands are blocked as a group. If any creatures with banding you control are blocking or being blocked by a creature, you divide that creature's combat damage, not its controller, among any of the creatures it's being blocked by or is blocking.)

Wall of Tanglecord

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

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.

Tower Defense

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

Crashing Drawbridge

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

Tetsuko Umezawa, Fugitive

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

Shield Sphere

Defender
Whenever Shield Sphere blocks, put a -0/-1 counter on it.

Jeskai Barricade

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

Aegis of the Heavens

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

Shield-Wall Sentinel

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

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.

Wall of Runes

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

Wall of Frost

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

Hover Barrier

Wall of Stolen Identity

You may have Wall of Stolen Identity enter the battlefield 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.

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.

Axebane Guardian

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

Wall of Denial

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

Bar the Door

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

Vine Trellis

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

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.)

Sunscape Familiar

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

Stalwart Shield-Bearers

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

Arcades, the Strategist

Flying, vigilance
Whenever a creature with defender enters the battlefield under your control, 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.

Another Round

Exile any number of creatures you control, then return them to the battlefield under their owner's control. Then repeat this process X more times.

Perimeter Captain

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

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

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.

Overgrown Battlement

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

Vault 75: Middle School

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Exile all creatures with power 4 or greater.
II, III — Put a +1/+1 counter on each creature you control.