Lightmine Field

Whenever one or more creatures attack, this enchantment deals damage to each of those creatures equal to the number of attacking creatures.

Isshin, Two Heavens as One

If a creature attacking causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Flawless Maneuver

If you control a commander, you may cast this spell without paying its mana cost.
Creatures you control gain indestructible until end of turn.

Dolmen Gate

Prevent all combat damage that would be dealt to attacking creatures you control.

Merchant of Truth

Flying
Whenever a nontoken creature you control dies, investigate.
Clues you control have exalted. (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn for each instance of exalted among permanents you control.)

Angelic Exaltation

Whenever a creature you control attacks alone, it gets +X/+X until end of turn, where X is the number of creatures you control.

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Norika Yamazaki, the Poet

Vigilance
Whenever a Samurai or Warrior you control attacks alone, you may cast target enchantment card from your graveyard this turn.

Swords to Plowshares

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

Lizard Blades

Double strike
Equipped creature has double strike.
Reconfigure {2} ({2}: Attach to target creature you control; or unattach from a creature. Reconfigure only as a sorcery. While attached, this isn't a creature.)

Slayers' Stronghold

{T}: Add {C}.
{R}{W}, {T}: Target creature gets +2/+0 and gains vigilance and haste until end of turn.

Reliquary Tower

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

Sublime Archangel

Flying
Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)
Other creatures you control have exalted. (If a creature has multiple instances of exalted, each triggers separately.)

Sigiled Paladin

First strike
Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)

Akrasan Squire

Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)

Sol Ring

Helm of the Host

At the beginning of combat on your turn, create a token that's a copy of equipped creature, except the token isn't legendary. That token gains haste.
Equip {5}

Cathedral of War

This land enters tapped.
Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)
{T}: Add {C}.

Rammas Echor, Ancient Shield

Whenever you cast your second spell each turn, draw a card, then create a 0/3 white Wall creature token with defender.
At the beginning of combat on your turn, creatures you control with defender gain exalted until end of turn. (Whenever a creature you control attacks alone, it gets +1/+1 until end of turn for each instance of exalted among permanents you control.)

Duskmantle Prowler

Haste (This creature can attack and {T} as soon as it comes under your control.)
Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)

Silent Arbiter

No more than one creature can attack each combat.
No more than one creature can block each combat.

Battlegrace Angel

Flying
Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)
Whenever a creature you control attacks alone, it gains lifelink until end of turn.

Urborg, Tomb of Yawgmoth

Each land is a Swamp in addition to its other land types.

Goblin Champion

Haste
Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)

Guardians of Akrasa

Defender (This creature can't attack.)
Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)

Despark

Exile target permanent with mana value 4 or greater.

Knight of Infamy

Protection from white (This creature can't be blocked, targeted, dealt damage, or enchanted by anything white.)
Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)

Shadowspear

Equipped creature gets +1/+1 and has trample and lifelink.
{1}: Permanents your opponents control lose hexproof and indestructible until end of turn.
Equip {2}

Servant of Nefarox

Peerless Samurai

Menace (This creature can't be blocked except by two or more creatures.)
Whenever a Samurai or Warrior you control attacks alone, the next spell you cast this turn costs {1} less to cast.

Angelic Benediction

Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)
Whenever a creature you control attacks alone, you may tap target creature.

Sigil of Valor

Whenever equipped creature attacks alone, it gets +1/+1 until end of turn for each other creature you control.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Brave the Sands

Creatures you control have vigilance.
Each creature you control can block an additional creature each combat.

Raiyuu, Storm's Edge

First strike
Whenever a Samurai or Warrior you control attacks alone, untap it. If it's the first combat phase of the turn, there is an additional combat phase after this phase.

The Reaver Cleaver

Equipped creature gets +1/+1 and has trample and "Whenever this creature deals combat damage to a player or planeswalker, create that many Treasure tokens."
Equip {3}

Knight of Glory

Protection from black (This creature can't be blocked, targeted, dealt damage, or enchanted by anything black.)
Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Krenko, Tin Street Kingpin

Whenever Krenko attacks, put a +1/+1 counter on it, then create a number of 1/1 red Goblin creature tokens equal to Krenko's power.

Nefarox, Overlord of Grixis

Flying
Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)
Whenever Nefarox attacks alone, defending player sacrifices a creature of their choice.

Anguished Unmaking

Exile target nonland permanent. You lose 3 life.

Vault of the Archangel

{T}: Add {C}.
{2}{W}{B}, {T}: Creatures you control gain deathtouch and lifelink until end of turn.

Generous Gift

Destroy target permanent. Its controller creates a 3/3 green Elephant creature token.

Karlach, Fury of Avernus

Whenever you attack, if it's the first combat phase of the turn, untap all attacking creatures. They gain first strike until end of turn. After this phase, there is an additional combat phase.
Choose a Background (You can have a Background as a second commander.)

Order of Sacred Dusk

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.)
Flying, lifelink, haste
Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)
Other Vampires you control have exalted.

Aven Squire

Flying
Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)

Ornithopter of Paradise

Vindicate

Idolized

Enchant creature
Enchanted creature has "Whenever this creature attacks alone, it gets +X/+X until end of turn, where X is the number of nonland permanents you control."

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}.

Heiko Yamazaki, the General

Trample
Whenever a Samurai or Warrior you control attacks alone, you may cast target artifact card from your graveyard this turn.

Duty-Bound Dead

Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)
{3}{B}: Regenerate this creature. (The next time this creature would be destroyed this turn, instead tap it, remove it from combat, and heal all damage on it.)