Wall of Frost

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

Cinder Wall

Defender
When this creature blocks, destroy it at end of combat.

Shifting Wall

Defender (This creature can't attack.)
This creature enters with X +1/+1 counters on it.

Tidal Wave

Create a 5/5 blue Wall creature token with defender. Sacrifice it at the beginning of the next end step.

Coral Barrier

Defender (This creature can't attack.)
When this creature enters, create a 1/1 blue Squid creature token with islandwalk. (It can't be blocked as long as defending player controls an Island.)

Plains

Puca's Mischief

At the beginning of your upkeep, you may exchange control of target nonland permanent you control and target nonland permanent an opponent controls with equal or lesser mana value.

Switcheroo

Exchange control of two target creatures.

Mountain

Wall of Fire

Defender (This creature can't attack.)
{R}: This creature gets +1/+0 until end of turn.

Goblin Digging Team

{T}, Sacrifice this creature: Destroy target Wall.

The Birth of Meletis

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Search your library for a basic Plains card, reveal it, put it into your hand, then shuffle.
II — Create a 0/4 colorless Wall artifact creature token with defender.
III — You gain 2 life.

Excavated Wall

Defender
{1}, {T}: Mill a card. (Put the top card of your library into your graveyard.)

Sudden Substitution

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Exchange control of target noncreature spell and target creature. Then the spell's controller may choose new targets for it.

Teyo, the Shieldmage

You have hexproof. (You can't be the target of spells or abilities your opponents control.)
−2: Create a 0/3 white Wall creature token with defender.

Dwarven Demolition Team

Island

Wall of Kelp

Defender (This creature can't attack.)
{U}{U}, {T}: Create a 0/1 blue Plant Wall creature token with defender named Kelp.