Ephemeral Shields

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Target creature gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Shieldmage Elder

Tap two untapped Clerics you control: Prevent all damage target creature would deal this turn.
Tap two untapped Wizards you control: Prevent all damage target spell would deal this turn.

White Shield Crusader

Protection from black
{W}: White Shield Crusader gains flying until end of turn.
{W}{W}: White Shield Crusader gets +1/+0 until end of turn.

Kithkin Shielddare

{W}, {T}: Target blocking creature gets +2/+2 until end of turn.

Teyo's Lightshield

When Teyo's Lightshield enters, put a +1/+1 counter on target creature you control.

Angelic Shield

Creatures you control get +0/+1.
Sacrifice Angelic Shield: Return target creature to its owner's hand.

Dispersal Shield

Counter target spell if its mana value is less than or equal to the highest mana value among permanents you control.

Haazda Shield Mate

At the beginning of your upkeep, sacrifice Haazda Shield Mate unless you pay {W}{W}.
{W}: The next time a source of your choice would deal damage to you this turn, prevent that damage.

Mourner's Shield

Imprint — When Mourner's Shield enters, you may exile target card from a graveyard.
{2}, {T}: Prevent all damage that would be dealt this turn by a source of your choice that shares a color with the exiled card.

Plains

Boros Fury-Shield

Prevent all combat damage that would be dealt by target attacking or blocking creature this turn. If {R} was spent to cast this spell, Boros Fury-Shield deals damage to that creature's controller equal to the creature's power.

Burrenton Shield-Bearers

Whenever Burrenton Shield-Bearers attacks, target creature gets +0/+3 until end of turn.

Shield of Kaldra

Equipment named Sword of Kaldra, Shield of Kaldra, and Helm of Kaldra have indestructible.
Equipped creature has indestructible. (Damage and effects that say "destroy" don't destroy it.)
Equip {4}

Spectral Shield

Enchant creature
Enchanted creature gets +0/+2 and can't be the target of spells.

Pariah's Shield

All damage that would be dealt to you is dealt to equipped creature instead.
Equip {3}

Sol Ring

Island

Shield of the Avatar

If a source would deal damage to equipped creature, prevent X of that damage, where X is the number of creatures you control.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Stalwart Shield-Bearers

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

Valkmira, Protector's Shield

If a source an opponent controls would deal damage to you or a permanent you control, prevent 1 of that damage.
Whenever you or another permanent you control becomes the target of a spell or ability an opponent controls, counter that spell or ability unless its controller pays {1}.

Reidane, God of the Worthy

Flying, vigilance
Snow lands your opponents control enter tapped.
Noncreature spells your opponents cast with mana value 4 or greater cost {2} more to cast.

Reidane, God of the Worthy // Valkmira, Protector's Shield

Shield of Duty and Reason

Enchant creature
Enchanted creature has protection from green and from blue.

Mirror Shield

Equipped creature gets +0/+2 and has hexproof and "Whenever a creature with deathtouch blocks or becomes blocked by this creature, destroy that creature."
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Shield of the Realm

If a source would deal damage to equipped creature, prevent 2 of that damage.
Equip {1}

Faith's Shield

Target permanent you control gains protection from the color of your choice until end of turn.
Fateful hour — If you have 5 or less life, instead you and each permanent you control gain protection from the color of your choice until end of turn.

Wall of Shields

Defender (This creature can't attack.)
Banding (If any creatures with banding you control are blocking a creature, you divide that creature's combat damage, not its controller, among any of the creatures it's being blocked by.)

Aethershield Artificer

At the beginning of combat on your turn, target artifact creature you control gets +2/+2 and gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Shieldmage Advocate

{T}: Return target card from an opponent's graveyard to their hand. Prevent all damage that would be dealt to any target this turn by a source of your choice.

Consul's Shieldguard

When Consul's Shieldguard enters, you get {E}{E} (two energy counters).
Whenever Consul's Shieldguard attacks, you may pay {E}. If you do, another target attacking creature gains indestructible until end of turn.

Shield of the Righteous

Equipped creature gets +0/+2 and has vigilance.
Whenever equipped creature blocks a creature, that creature doesn't untap during its controller's next untap step.
Equip {2}

Shell Shield

Kicker {1} (You may pay an additional {1} as you cast this spell.)
Target creature you control gets +0/+3 until end of turn. If this spell was kicked, that creature also gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Shield Wall

Creatures you control get +0/+2 until end of turn.

Shield Dancer

{2}{W}: The next time target attacking creature would deal combat damage to Shield Dancer this turn, that creature deals that damage to itself instead.

Floating Shield

Enchant creature
As Floating Shield enters, choose a color.
Enchanted creature has protection from the chosen color. This effect doesn't remove Floating Shield.
Sacrifice Floating Shield: Target creature gains protection from the chosen color until end of turn.

Staunch Shieldmate

Vanguard's Shield

Equipped creature gets +0/+3 and can block an additional creature each combat.
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)

Linvala, Shield of Sea Gate

Flying
At the beginning of combat on your turn, if you have a full party, choose target nonland permanent an opponent controls. Until your next turn, it can't attack or block, and its activated abilities can't be activated.
Sacrifice Linvala: Choose hexproof or indestructible. Creatures you control gain that ability until end of turn.

Shields of Velis Vel

Changeling (This card is every creature type.)
Creatures target player controls get +0/+1 and gain all creature types until end of turn.

Shield Sphere

Defender
Whenever Shield Sphere blocks, put a -0/-1 counter on it.

Battershield Warrior

Boast — {1}{W}: Creatures you control get +1/+1 until end of turn. (Activate only if this creature attacked this turn and only once each turn.)

Drogskol Shieldmate

Flash (You may cast this spell any time you could cast an instant.)
When Drogskol Shieldmate enters, other creatures you control get +0/+1 until end of turn.

Elgaud Shieldmate

Soulbond (You may pair this creature with another unpaired creature when either enters. They remain paired for as long as you control both of them.)
As long as Elgaud Shieldmate is paired with another creature, both creatures have hexproof. (They can't be the targets of spells or abilities your opponents control.)

Shield Bearer

Banding (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 blocking or being blocked by a creature, you divide that creature's combat damage, not its controller, among any of the creatures it's being blocked by or is blocking.)

Kry Shield

{2}, {T}: Prevent all damage that would be dealt this turn by target creature you control. That creature gets +0/+X until end of turn, where X is its mana value.

Accorder's Shield

Equipped creature gets +0/+3 and has vigilance. (Attacking doesn't cause it to tap.)
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)

Nyxborn Shieldmate

Bestow {2}{W} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached to a creature.)
Enchanted creature gets +1/+2.

Shielded Aether Thief

Flash (You may cast this spell any time you could cast an instant.)
Whenever Shielded Aether Thief blocks, you get {E} (an energy counter).
{T}, Pay {E}{E}{E}: Draw a card.

Screaming Shield

Equipped creature gets +0/+3 and has "{2}, {T}: Target player mills three cards."
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)

Rhystic Shield

Creatures you control get +0/+1 until end of turn. They get an additional +0/+2 until end of turn unless any player pays {2}.

Order of the White Shield

Protection from black
{W}: Order of the White Shield gains first strike until end of turn.
{W}{W}: Order of the White Shield gets +1/+0 until end of turn.

Cathar's Shield

Equipped creature gets +0/+3 and has vigilance.
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)

Shielded Passage

Prevent all damage that would be dealt to target creature this turn.

Shield Mare

Shield Mare can't be blocked by red creatures.
When Shield Mare enters or becomes the target of a spell or ability an opponent controls, you gain 3 life.

Shield of the Ages

{2}: Prevent the next 1 damage that would be dealt to you this turn.

Spirit Shield

You may choose not to untap Spirit Shield during your untap step.
{2}, {T}: Target creature gets +0/+2 for as long as Spirit Shield remains tapped.

Shield Mate

Sacrifice Shield Mate: Target creature gets +0/+4 until end of turn.

Delaying Shield

If damage would be dealt to you, put that many delay counters on Delaying Shield instead.
At the beginning of your upkeep, remove all delay counters from Delaying Shield. For each delay counter removed this way, you lose 1 life unless you pay {1}{W}.

Makindi Shieldmate

Defender
Whenever Makindi Shieldmate or another Ally you control enters, you may put a +1/+1 counter on Makindi Shieldmate.

Ethersworn Shieldmage

Flash
When Ethersworn Shieldmage enters, prevent all damage that would be dealt to artifact creatures this turn.

Beskir Shieldmate

When Beskir Shieldmate dies, create a 1/1 white Human Warrior creature token.

Shieldhide Dragon

Flying, lifelink
Megamorph {5}{W}{W} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its megamorph cost and put a +1/+1 counter on it.)
When Shieldhide Dragon is turned face up, put a +1/+1 counter on each other Dragon creature you control.

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.

Shielded by Faith

Enchant creature
Enchanted creature has indestructible.
Whenever a creature enters, you may attach Shielded by Faith to that creature.