Perimeter Captain

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

Wall of Tanglecord

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

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.)

Wall of Blossoms

Defender
When Wall of Blossoms enters the battlefield, draw a card.

Hover Barrier

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

Wall of Omens

Defender
When Wall of Omens enters the battlefield, draw a card.

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.

Crashing Drawbridge

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

Wall of Denial

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

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.

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.

Sunscape Familiar

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

Tower Defense

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

Stalwart Shield-Bearers

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

Overgrown Battlement

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

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.

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.

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.