Overgrown Battlement

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

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.

Perimeter Captain

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

Stalwart Shield-Bearers

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

Wall of Vines

Defender (This creature can't attack.)
Reach (This creature can block creatures with flying.)

Suspicious Bookcase

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

Guardians of Meletis

Towering Viewpoint

Defender, reach
Leap of Faith — {3}: Target creature gains flying until end of turn.

Primal Clay

As this creature enters, it becomes your choice of a 3/3 artifact creature, a 2/2 artifact creature with flying, or a 1/6 Wall artifact creature with defender in addition to its other types. (A creature with defender can't attack.)

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.)

Stoic Ephemera

Defender (This creature can't attack.)
Flying
When this creature blocks, sacrifice it at end of combat.

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.)

Angelic Wall

Defender (This creature can't attack.)
Flying

Souls of the Faultless

Defender (This creature can't attack.)
Whenever this creature is dealt combat damage, you gain that much life and attacking player loses that much life.

Geist of the Lonely Vigil

Defender, flying
Delirium — This creature can attack as though it didn't have defender as long as there are four or more card types among cards in your graveyard.

Crenellated Wall

Defender (This creature can't attack.)
{T}: Target creature gets +0/+4 until end of turn.

Dragon Throne of Tarkir

Equipped creature has defender and "{2}, {T}: Other creatures you control gain trample and get +X/+X until end of turn, where X is this creature's power."
Equip {3}

Portcullis Vine

Defender (This creature can't attack.)
{2}, {T}, Sacrifice a creature with defender: Draw a card.

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.

Felothar the Steadfast

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.
{3}, {T}, Sacrifice another creature: Draw cards equal to the sacrificed creature's toughness, then discard cards equal to its power.