Aetherflame Wall

Defender
Aetherflame Wall can block creatures with shadow as though they didn't have shadow.
{R}: Aetherflame Wall gets +1/+0 until end of turn.

Joven's Tools

{4}, {T}: Target creature can't be blocked this turn except by Walls.

Cloak of Invisibility

Enchant creature
Enchanted creature has phasing and can't be blocked except by Walls. (It phases in or out before its controller untaps during each of their untap steps. While it's phased out, it's treated as though it doesn't exist.)

Aurification

Whenever a creature deals damage to you, put a gold counter on it.
Each creature with a gold counter on it is a Wall in addition to its other creature types and has defender. (Those creatures can't attack.)
When Aurification leaves the battlefield, remove all gold counters from all creatures.

Animate Wall

Enchant Wall
Enchanted Wall can attack as though it didn't have defender.

Acidic Dagger

{4}, {T}: Whenever target creature deals combat damage to a non-Wall creature this turn, destroy that non-Wall creature. When the targeted creature leaves the battlefield this turn, sacrifice Acidic Dagger. Activate only before blockers are declared.

Invisibility

Enchant creature
Enchanted creature can't be blocked except by Walls.

Blaster Mage

{R}, {T}, Discard a card: Destroy target Wall.

Amaranthine Wall

Defender
{2}: Amaranthine Wall gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Ali Baba

Pramikon, Sky Rampart

Flying, defender
As Pramikon, Sky Rampart enters, choose left or right.
Each player may attack only the nearest opponent in the chosen direction and planeswalkers controlled by that opponent.

Battering Ram

At the beginning of combat on your turn, Battering Ram gains banding until end of combat. (Any creatures with banding, and up to one without, can attack in a band. Bands are blocked as a group. If any creatures with banding you control are being blocked by a creature, you divide that creature's combat damage, not its controller, among any of the creatures it's blocking.)
Whenever Battering Ram becomes blocked by a Wall, destroy that Wall at end of combat.

Blow Your House Down

Up to three target creatures can't block this turn. Destroy any of them that are Walls.

Chaos Charm

Choose one —
• Destroy target Wall.
• Chaos Charm deals 1 damage to target creature.
• Target creature gains haste until end of turn.