Aura Blast

Viridian Claw

Equipped creature gets +1/+0 and has first strike.
Equip {1}

Ethereal Armor

Enchant creature
Enchanted creature gets +1/+1 for each enchantment you control and has first strike.

Soul of Theros

Vigilance
{4}{W}{W}: Creatures you control get +2/+2 and gain first strike and lifelink until end of turn.
{4}{W}{W}, Exile Soul of Theros from your graveyard: Creatures you control get +2/+2 and gain first strike and lifelink until end of turn.

Odric, Lunarch Marshal

At the beginning of each combat, creatures you control gain first strike until end of turn if a creature you control has first strike. The same is true for flying, deathtouch, double strike, haste, hexproof, indestructible, lifelink, menace, reach, skulk, trample, and vigilance.

Hyena Umbra

Enchant creature
Enchanted creature gets +1/+1 and has first strike.
Umbra armor (If enchanted creature would be destroyed, instead remove all damage from it and destroy this Aura.)

Youthful Knight

Dragon's Eye Sentry

Jousting Lance

Equipped creature gets +2/+0.
As long as it's your turn, equipped creature has first strike.
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)

Glorious Anthem

Plains

No-Dachi

Equipped creature gets +2/+0 and has first strike.
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)

Arcane Encyclopedia

Military Discipline

Flash
Enchant creature
When Military Discipline enters the battlefield, enchanted creature gains first strike until end of turn.
Enchanted creature gets +1/+0.

Lossarnach Captain

First strike
Whenever Lossarnach Captain or another Human enters the battlefield under your control, tap target creature an opponent controls.
At the beginning of your upkeep, create a 1/1 white Human Soldier creature token.

Charge

Creatures you control get +1/+1 until end of turn.

Skillful Lunge

Target creature gets +2/+0 and gains first strike until end of turn.

Longbow Archer

First strike; reach (This creature can block creatures with flying.)

Rally Maneuver

Target creature gets +2/+0 and gains first strike until end of turn. Up to one other target creature gets +0/+2 and gains lifelink until end of turn.

Kwende, Pride of Femeref

Double strike
Creatures you control with first strike have double strike.

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Unbreakable Formation

Creatures you control gain indestructible until end of turn.
Addendum — If you cast this spell during your main phase, put a +1/+1 counter on each of those creatures and they gain vigilance until end of turn.

Bonder's Ornament

{T}: Add one mana of any color.
{4}, {T}: Each player who controls a permanent named Bonder's Ornament draws a card.

Guardians' Pledge

White creatures you control get +2/+2 until end of turn.

Shepherd of the Lost

Dictate of Heliod

Syr Alin, the Lion's Claw

First strike
Whenever Syr Alin, the Lion's Claw attacks, other creatures you control get +1/+1 until end of turn.

Sword of the Animist

Equipped creature gets +1/+1.
Whenever equipped creature attacks, you may search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
Equip {2}

Benalish Marshal

Sword of Vengeance

Equipped creature gets +2/+0 and has first strike, vigilance, trample, and haste.
Equip {3}

Runechanter's Pike

Equipped creature has first strike and gets +X/+0, where X is the number of instant and sorcery cards in your graveyard.
Equip {2}

Commanding Presence

Enchant creature
Enchanted creature gets +2/+2 and has first strike and "Whenever this creature deals combat damage to a player, create a 1/1 white Human Soldier creature token."

Force of Virtue

If it's not your turn, you may exile a white card from your hand rather than pay this spell's mana cost.
Flash
Creatures you control get +1/+1.

Warded Battlements

Defender (This creature can't attack.)
Attacking creatures you control get +1/+0.

Knight Exemplar

First strike (This creature deals combat damage before creatures without first strike.)
Other Knight creatures you control get +1/+1 and have indestructible. (Damage and effects that say "destroy" don't destroy them.)

Ballynock Cohort

First strike
Ballynock Cohort gets +1/+1 as long as you control another white creature.

Cartouche of Solidarity

Enchant creature you control
When Cartouche of Solidarity enters the battlefield, create a 1/1 white Warrior creature token with vigilance.
Enchanted creature gets +1/+1 and has first strike.

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Letter of Acceptance

{T}: Add one mana of any color.
{2}, {T}, Sacrifice Letter of Acceptance: Draw a card.

Marble Diamond

Marble Diamond enters the battlefield tapped.
{T}: Add {W}.

Hall of Triumph

As Hall of Triumph enters the battlefield, choose a color.
Creatures you control of the chosen color get +1/+1.

Nightguard Patrol

Honored Heirloom

{T}: Add one mana of any color.
{2}, {T}: Exile target card from a graveyard.

Haunted Guardian

Consul's Lieutenant

First strike
Renown 1 (When this creature deals combat damage to a player, if it isn't renowned, put a +1/+1 counter on it and it becomes renowned.)
Whenever Consul's Lieutenant attacks, if it's renowned, other attacking creatures you control get +1/+1 until end of turn.

Chapel Shieldgeist

Flying, first strike
Each creature you control has ward {1}. (Whenever it becomes the target of a spell or ability an opponent controls, counter it unless that player pays {1}.)
If Chapel Shieldgeist would be put into a graveyard from anywhere, exile it instead.

Chaplain of Alms

First strike
Ward {1} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {1}.)
Disturb {3}{W} (You may cast this card from your graveyard transformed for its disturb cost.)

Chaplain of Alms // Chapel Shieldgeist

Maul of the Skyclaves

When Maul of the Skyclaves enters the battlefield, attach it to target creature you control.
Equipped creature gets +2/+2 and has flying and first strike.
Equip {2}{W}{W}

Kor Scythemaster

Kor Scythemaster has first strike as long as it's attacking.

Disenchant

Sanctified Charge

Creatures you control get +2/+1 until end of turn. White creatures you control also gain first strike until end of turn. (They deal combat damage before creatures without first strike.)

Mana Geode

When Mana Geode enters the battlefield, scry 1.
{T}: Add one mana of any color.

Enchant creature
Enchanted creature gets +2/+2, has first strike, and is a Knight in addition to its other types. (It deals combat damage before creatures without first strike.)

Attended Knight

First strike
When Attended Knight enters the battlefield, create a 1/1 white Soldier creature token.

Space Marine Scout

First strike, vigilance
Concealed Position — When Space Marine Scout enters the battlefield, if an opponent controls more lands than you, you may search your library for a Plains card, put it onto the battlefield tapped, then shuffle.

Benalish Knight

Flash (You may cast this spell any time you could cast an instant.)
First strike (This creature deals combat damage before creatures without first strike.)

Scepter of Dominance

Odric, Master Tactician

First strike (This creature deals combat damage before creatures without first strike.)
Whenever Odric, Master Tactician and at least three other creatures attack, you choose which creatures block this combat and how those creatures block.

Bonesplitter

Danitha Capashen, Paragon

First strike, vigilance, lifelink
Aura and Equipment spells you cast cost {1} less to cast.

Heraldic Banner

As Heraldic Banner enters the battlefield, choose a color.
Creatures you control of the chosen color get +1/+0.
{T}: Add one mana of the chosen color.

Ravnica at War

Thalia's Lancers

First strike
When Thalia's Lancers enters the battlefield, you may search your library for a legendary card, reveal it, put it into your hand, then shuffle.

Hope Against Hope

Enchant creature
Enchanted creature gets +1/+1 for each creature you control.
As long as enchanted creature is a Human, it has first strike.

Face of Divinity

Enchant creature
Enchanted creature gets +2/+2.
As long as another Aura is attached to enchanted creature, it has first strike and lifelink.

Elite Inquisitor

First strike, vigilance
Protection from Vampires, from Werewolves, and from Zombies

Always Watching

Nontoken creatures you control get +1/+1 and have vigilance.

Paladin Class

(Gain the next level as a sorcery to add its ability.)
Spells your opponents cast during your turn cost {1} more to cast.
{2}{W}: Level 2
Creatures you control get +1/+1.
{4}{W}: Level 3
Whenever you attack, until end of turn, target attacking creature gets +1/+1 for each other attacking creature and gains double strike.

Make a Stand

Creatures you control get +1/+0 and gain indestructible until end of turn. (Damage and effects that say "destroy" don't destroy them.)