Perimeter Captain

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

Fortified Rampart

Wall of Blossoms

Defender
When Wall of Blossoms enters, draw a card.

Glacial Wall

Wall of Denial

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

Axebane Guardian

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

Hornet Nest

Defender (This creature can't attack.)
Whenever Hornet Nest is dealt damage, create that many 1/1 green Insect creature tokens with flying and deathtouch. (Any amount of damage a creature with deathtouch deals to a creature is enough to destroy it.)

Bant Panorama

{T}: Add {C}.
{1}, {T}, Sacrifice Bant Panorama: Search your library for a basic Forest, Plains, or Island card, put it onto the battlefield tapped, then shuffle.

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.

Island

Riptide Turtle

Sunscape Familiar

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

Gomazoa

Defender, flying
{T}: Put Gomazoa and each creature it's blocking on top of their owners' libraries, then those players shuffle.

Plains

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.

Stalwart Shield-Bearers

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

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.

Towering Titan

Towering Titan 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.

Tower Defense

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

Command Tower

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

Wall of Frost

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

Wall of Omens

Defender
When Wall of Omens enters, draw a card.

Hover Barrier

Forest

Bar the Door

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

Floriferous Vinewall

Defender
When Floriferous Vinewall enters, look at the top six cards of your library. You may reveal a land card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.