Selfless Samurai

Whenever a Samurai or Warrior you control attacks alone, it gains lifelink until end of turn.
Sacrifice this creature: Another target creature you control gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Mountain

Imperial Oath

Create three 2/2 white Samurai creature tokens with vigilance. Scry 3.

Devoted Retainer

Bushido 1 (Whenever this creature blocks or becomes blocked, it gets +1/+1 until end of turn.)

Seifer Almasy

Whenever a creature you control attacks alone, it gains double strike until end of turn.
Fire Cross — Whenever Seifer Almasy deals combat damage to a player, you may cast target instant or sorcery card with mana value 3 or less from your graveyard without paying its mana cost. If that spell would be put into your graveyard, exile it instead.

Boros Locket

{T}: Add {R} or {W}.
{R/W}{R/W}{R/W}{R/W}, {T}, Sacrifice this artifact: Draw two cards.

Explosive Entry

Destroy up to one target artifact. Put a +1/+1 counter on up to one target creature.

Akki Ember-Keeper

Whenever a nontoken modified creature you control dies, create a 1/1 colorless Spirit creature token. (Equipment, Auras you control, and counters are modifications.)

Ancestral Katana

Whenever a Samurai or Warrior you control attacks alone, you may pay {1}. When you do, attach this Equipment to it.
Equipped creature gets +2/+1.
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)

Sky-Blessed Samurai

Affinity for enchantments (This spell costs {1} less to cast for each enchantment you control.)
Flying

Crackling Emergence

Enchant land you control
Enchanted land is a 3/3 red Spirit creature with haste. It's still a land.
If enchanted land would be destroyed, instead sacrifice this Aura and that land gains indestructible until end of turn.

Eiganjo Exemplar

Whenever a Samurai or Warrior you control attacks alone, it gets +1/+1 until end of turn.

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.

Plains

Wanderer's Intervention

Wanderer's Intervention deals 4 damage to target attacking or blocking creature.

Tempered in Solitude

Whenever a creature you control attacks alone, exile the top card of your library. You may play that card this turn.

Kitsune Ace

Whenever a Vehicle you control attacks, choose one —
• That Vehicle gains first strike until end of turn.
• Untap this creature.

Thundersteel Colossus

Trample, haste
Crew 2 (Tap any number of creatures you control with total power 2 or more: This Vehicle becomes an artifact creature until end of turn.)

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.

Sunblade Samurai

Vigilance (Attacking doesn't cause this creature to tap.)
Channel — {2}, Discard this card: Search your library for a basic Plains card, reveal it, put it into your hand, then shuffle. You gain 2 life.

Imperial Subduer

Whenever a Samurai or Warrior you control attacks alone, tap target creature you don't control.

Reinforced Ronin

Haste
At the beginning of your end step, return this creature to its owner's hand.
Channel — {1}{R}, Discard this card: Draw a card.

Akrasan Squire

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

Blade-Blizzard Kitsune

Ninjutsu {3}{W} ({3}{W}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Double strike

Golden-Tail Disciple

Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Banishing Slash

Destroy up to one target artifact, enchantment, or tapped creature. Then if you control an artifact and an enchantment, create a 2/2 white Samurai creature token with vigilance.

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.

Brute Suit

Vigilance
Crew 1 (Tap any number of creatures you control with total power 1 or more: This Vehicle becomes an artifact creature until end of turn.)

Asari Captain

Haste
Whenever a Samurai or Warrior you control attacks alone, it gets +1/+0 until end of turn for each Samurai or Warrior you control.

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.

Akki Ronin

Whenever a Samurai or Warrior you control attacks alone, you may discard a card. If you do, draw a card.

Seven-Tail Mentor

When this creature enters or dies, put a +1/+1 counter on target creature or Vehicle you control.