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.

Guardians of Oboro

Defender
Modified creatures you control can attack as though they didn't have defender. (Equipment, Auras you control, and counters are modifications.)

Roving Keep

Defender
{7}: Roving Keep gets +2/+0 and gains trample until end of turn. It can attack this turn as though it didn't have defender.

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.

Sinner's Judgment

Enchant player
At the beginning of your upkeep, put a judgment counter on Sinner's Judgment. Then if there are three or more judgment counters on it, enchanted player loses the game.
If Sinner's Judgment would be put into a graveyard from anywhere, exile it instead.

Faithbound Judge

Defender, flying, vigilance
At the beginning of your upkeep, if Faithbound Judge has two or fewer judgment counters on it, put a judgment counter on it.
As long as Faithbound Judge has three or more judgment counters on it, it can attack as though it didn't have defender.
Disturb {5}{W}{W}

Faithbound Judge // Sinner's Judgment

Coral Colony

Defender
{1}{U}, {T}: Target player mills X cards, where X is the number of creatures you control with defender. (To mill a card, a player puts the top card of their library into their graveyard.)

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.

Gargoyle Sentinel

Defender (This creature can't attack.)
{3}: Until end of turn, Gargoyle Sentinel loses defender and gains flying.

Overgrown Battlement

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

Consulate Skygate

Defender
Reach (This creature can block creatures with flying.)

Backstreet Bruiser

Defender
As long as there are two or more counters among creatures you control, Backstreet Bruiser can attack as though it didn't have defender.

Carven Caryatid

Defender (This creature can't attack.)
When Carven Caryatid enters, draw a card.

Errant, Street Artist

Flash
Defender, haste
{1}{U}, {T}: Copy target spell you control that wasn't cast. You may choose new targets for the copy.

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.

Reito Sentinel

Defender
When Reito Sentinel enters, target player mills three cards. (They put the top three cards of their library into their graveyard.)
{3}: Put target card from a graveyard on the bottom of its owner's library.

Drowsing Tyrannodon

Defender (This creature can't attack.)
As long as you control a creature with power 4 or greater, Drowsing Tyrannodon can attack as though it didn't have defender.