Spirit Mantle

Enchant creature
Enchanted creature gets +1/+1 and has protection from creatures.

Unquenchable Fury

Enchant creature
Enchanted creature has "Whenever this creature attacks, it deals X damage to defending player, where X is the number of cards in their hand."
When Unquenchable Fury is put into your graveyard from the battlefield, return it to your hand.

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.

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.

Wanderer's Intervention

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

Madcap Skills

Enchant creature
Enchanted creature gets +3/+0 and has menace.

Ethereal Armor

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

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.

Eiganjo Exemplar

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

Mountain

Imperial Subduer

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

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.