Stalwart Shield-Bearers

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

Wall of Frost

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

Sunscape Familiar

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

Crashing Drawbridge

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

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

Axebane Guardian

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

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.

Wall of Denial

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

Perimeter Captain

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

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.

Tetsuko Umezawa, Fugitive

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

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.

Hover Barrier

Lush Portico

({T}: Add {G} or {W}.)
Lush Portico enters tapped.
When Lush Portico enters, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Wall of Omens

Defender
When Wall of Omens enters, draw a card.

Tower Defense

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

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.

Overgrown Battlement

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

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.

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.