Unexpected Windfall

As an additional cost to cast this spell, discard a card.
Draw two cards and create two Treasure tokens. (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Sejiri Glacier

Sejiri Glacier enters tapped.
{T}: Add {W}.

Sejiri Shelter

Target creature you control gains protection from the color of your choice until end of turn.

Sejiri Shelter // Sejiri Glacier

Rumor Gatherer

Alliance — Whenever another creature you control enters, scry 1. If this is the second time this ability has resolved this turn, draw a card instead.

Signal Pest

Battle cry (Whenever this creature attacks, each other attacking creature gets +1/+0 until end of turn.)
Signal Pest can't be blocked except by creatures with flying or reach.

Valorous Stance

Choose one —
• Target creature gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)
• Destroy target creature with toughness 4 or greater.

Unbounded Potential

Choose one —
• Put a +1/+1 counter on each of up to two target creatures.
• Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)
Entwine {3}{W} (Choose both if you pay the entwine cost.)

Mountain

Spirited Companion

When Spirited Companion enters, draw a card.

Gather the Townsfolk

Create two 1/1 white Human creature tokens.
Fateful hour — If you have 5 or less life, create five of those tokens instead.

Grateful Apparition

Flying
Whenever Grateful Apparition deals combat damage to a player or planeswalker, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Loyal Apprentice

Haste
Lieutenant — At the beginning of combat on your turn, if you control your commander, create a 1/1 colorless Thopter artifact creature token with flying. That token gains haste until end of turn.

Volt Charge

Volt Charge deals 3 damage to any target. Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Skyknight Vanguard

Flying
Whenever Skyknight Vanguard attacks, create a 1/1 white Soldier creature token that's tapped and attacking.

Legion Stronghold

Legion Stronghold enters tapped.
{T}: Add {R} or {W}.

Legion Leadership

Until end of turn, double target creature's power and it gains first strike.

Legion Leadership // Legion Stronghold

Reprieve

Return target spell to its owner's hand.
Draw a card.

Tori D'Avenant, Fury Rider

Vigilance, trample
Whenever Tori D'Avenant, Fury Rider attacks, all other attacking creatures you control get +1/+1 until end of turn. Other red attacking creatures you control gain trample until end of turn. Untap each other white attacking creature you control.

Landroval, Horizon Witness

Flying
Whenever two or more creatures you control attack a player, target attacking creature without flying gains flying until end of turn.

Thought Vessel

You have no maximum hand size.
{T}: Add {C}.

Bomber Corps

Battalion — Whenever Bomber Corps and at least two other creatures attack, Bomber Corps deals 1 damage to any target.

Sontaran General

Trample, haste
Battalion — Whenever Sontaran General and at least two other creatures attack, for each opponent, goad up to one target creature that player controls. Those creatures can't block this turn. (Until your next turn, they attack each combat if able and attack a player other than you if able.)

Grab the Prize

As an additional cost to cast this spell, discard a card.
Draw two cards. If the discarded card wasn't a land card, Grab the Prize deals 2 damage to each opponent.

Plains

Distract the Guards

Freerunning {1}{W} (You may cast this spell for its freerunning cost if you dealt combat damage to a player this turn with an Assassin or commander.)
Create three 1/1 white Human Rogue creature tokens.

Metastatic Evangel

Whenever another nontoken creature you control enters, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Frontier Warmonger

Whenever one or more creatures attack one of your opponents or a planeswalker they control, those creatures gain menace until end of turn.

Rip Apart

Choose one —
• Rip Apart deals 3 damage to target creature or planeswalker.
• Destroy target artifact or enchantment.

Goblin Instigator

When Goblin Instigator enters, create a 1/1 red Goblin creature token.

Craig Boone, Novac Guard

Reach, lifelink
One for My Baby — Whenever you attack with two or more creatures, put two quest counters on Craig Boone, Novac Guard. When you do, Craig Boone deals damage equal to the number of quest counters on it to up to one target creature unless that creature's controller has Craig Boone deal that much damage to them.

Wayfarer's Bauble

{2}, {T}, Sacrifice Wayfarer's Bauble: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Archetype of Aggression

Creatures you control have trample.
Creatures your opponents control lose trample and can't have or gain trample.

Impulsive Pilferer

When Impulsive Pilferer dies, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")
Encore {3}{R} ({3}{R}, Exile this card from your graveyard: For each opponent, create a token copy that attacks that opponent this turn if able. They gain haste. Sacrifice them at the beginning of the next end step. Activate only as a sorcery.)

Your Temple Is Under Attack

Choose one —
• Pray for Protection — Creatures you control gain indestructible until end of turn.
• Strike a Deal — You and target opponent each draw two cards.

Mentor of the Meek

Whenever another creature you control with power 2 or less enters, you may pay {1}. If you do, draw a card.

Syr Alin, the Lion's Claw

First strike (This creature deals combat damage before creatures without first strike.)
Whenever Syr Alin attacks, other creatures you control get +1/+1 until end of turn.

Taunting Kobold

Haste
Whenever Taunting Kobold attacks, goad target creature an opponent controls. (Until your next turn, that creature attacks each combat if able and attacks a player other than you if able.)

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Marble Diamond

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

Contagion Clasp

When Contagion Clasp enters, put a -1/-1 counter on target creature.
{4}, {T}: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Sunset Revelry

If an opponent has more life than you, you gain 4 life.
If an opponent controls more creatures than you, create two 1/1 white Human creature tokens.
If an opponent has more cards in hand than you, draw a card.

Sol Ring

Haazda Marshal

Whenever Haazda Marshal and at least two other creatures attack, create a 1/1 white Soldier creature token with lifelink.

Thrill of Possibility

As an additional cost to cast this spell, discard a card.
Draw two cards.

Kazuul, Tyrant of the Cliffs

Whenever a creature an opponent controls attacks, if you're the defending player, create a 3/3 red Ogre creature token unless that creature's controller pays {3}.

Overpowering Attack

Freerunning {2}{R} (You may cast this spell for its freerunning cost if you dealt combat damage to a player this turn with an Assassin or commander.)
Untap all creatures you control that attacked this turn. If it's your main phase, there is an additional combat phase after this phase, followed by an additional main phase.

Ezio, Brash Novice

Whenever Ezio, Brash Novice attacks, put a +1/+1 counter on it.
As long as Ezio has two or more counters on it, it has first strike and is an Assassin in addition to its other types.

Tyr's Blessing

Target creature gains indestructible until end of turn. (Then exile this card. You may cast the creature later from exile.)

Blessed Hippogriff

Flying
Whenever Blessed Hippogriff attacks, target attacking creature without flying gains flying until end of turn.

Blessed Hippogriff // Tyr's Blessing

Faithless Looting

Draw two cards, then discard two cards.
Flashback {2}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Boros Charm

Choose one —
• Boros Charm deals 4 damage to target player or planeswalker.
• Permanents you control gain indestructible until end of turn.
• Target creature gains double strike until end of turn.

Oketra's Monument

White creature spells you cast cost {1} less to cast.
Whenever you cast a creature spell, create a 1/1 white Warrior creature token with vigilance.

Charitable Levy

Noncreature spells cost {1} more to cast.
Whenever a player casts a noncreature spell, put a collection counter on Charitable Levy. Then if there are three or more collection counters on it, sacrifice it. If you do, draw a card, then you may search your library for a Plains card, put it onto the battlefield tapped, then shuffle.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Big Score

Impact Tremors

Whenever a creature you control enters, this enchantment deals 1 damage to each opponent.

Fire Diamond

Fire Diamond enters tapped.
{T}: Add {R}.

Arcane Signet

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

Silver Shroud Costume

Flash
When Silver Shroud Costume enters, attach it to target creature you control. That creature gains shroud until end of turn. (It can't be the target of spells or abilities.)
Equipped creature can't be blocked.
Equip {3}

Molten Gatekeeper

Whenever another creature you control enters, Molten Gatekeeper deals 1 damage to each opponent.
Unearth {R} ({R}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Valor's Reach Tag Team

Create two 3/2 red and white Warrior creature tokens with "Whenever this creature and at least one other creature token attack, put a +1/+1 counter on this creature."

Invasion of Kylem

(As a Siege enters, choose an opponent to protect it. You and others can attack it. When it's defeated, exile it, then cast it transformed.)
When Invasion of Kylem enters, up to two target creatures each get +2/+0 and gain vigilance and haste until end of turn.

Invasion of Kylem // Valor's Reach Tag Team

Stone of Erech

If a creature an opponent controls would die, exile it instead.
{2}, {T}, Sacrifice Stone of Erech: Exile target player's graveyard. Draw a card.

Heroic Reinforcements

Create two 1/1 white Soldier creature tokens. Until end of turn, creatures you control get +1/+1 and gain haste. (They can attack and {T} this turn.)

Hardened Escort

Whenever Hardened Escort attacks, another target creature you control gets +1/+0 and gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Dauntless Dismantler

Artifacts your opponents control enter tapped.
{X}{X}{W}, Sacrifice Dauntless Dismantler: Destroy each artifact with mana value X.

Rally at the Hornburg

Create two 1/1 white Human Soldier creature tokens. Humans you control gain haste until end of turn.

Selfless Savior

Sacrifice Selfless Savior: Another target creature you control gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Witch-Blessed Meadow

As Witch-Blessed Meadow enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {W}.

Witch Enchanter

When Witch Enchanter enters, destroy target artifact or enchantment an opponent controls.