Have

Plains

Call the Gatewatch

Search your library for a planeswalker card, reveal it, put it into your hand, then shuffle.

Furious Resistance

Target blocking creature gets +3/+0 and gains first strike until end of turn.

Mountain

Aether Membrane

Defender; reach (This creature can block creatures with flying.)
Whenever Aether Membrane blocks a creature, return that creature to its owner's hand at end of combat.

Pin to the Earth

Enchant creature
Enchanted creature gets -6/-0.

Ivory Mask

You have shroud. (You can't be the target of spells or abilities.)

Dazzling Reflection

You gain life equal to target creature's power. The next time that creature would deal damage this turn, prevent that damage.

Nivix Cyclops

Defender
Whenever you cast an instant or sorcery spell, Nivix Cyclops gets +3/+0 until end of turn and can attack this turn as though it didn't have defender.

Smite

Stalwart Shield-Bearers

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

Island

Thunder Strike

Target creature gets +2/+0 and gains first strike until end of turn. (It deals combat damage before creatures without first strike.)

Fog Bank

Defender (This creature can't attack.)
Flying
Prevent all combat damage that would be dealt to and dealt by this creature.

Weapon Surge

Target creature you control gets +1/+0 and gains first strike until end of turn.
Overload {1}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Chaplain's Blessing

Angelic Wall

Defender (This creature can't attack.)
Flying

Ludevic's Abomination

Ludevic's Test Subject

Defender
{1}{U}: Put a hatchling counter on Ludevic's Test Subject. Then if there are five or more hatchling counters on it, remove all of them and transform it.

Ludevic's Test Subject // Ludevic's Abomination

Wall of Frost

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

Fireball

This spell costs {1} more to cast for each target beyond the first.
Fireball deals X damage divided evenly, rounded down, among any number of targets.

Shock

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Mnemonic Wall

Defender
When Mnemonic Wall enters, you may return target instant or sorcery card from your graveyard to your hand.

Reverberate

Copy target instant or sorcery spell. You may choose new targets for the copy.

Wall of Swords

Gods Willing

Target creature you control gains protection from the color of your choice until end of turn. (It can't be blocked, targeted, dealt damage, enchanted, or equipped by anything of that color.)
Scry 1.

Wall of One Thousand Cuts

Defender, flying
{W}: Wall of One Thousand Cuts can attack this turn as though it didn't have defender.