Brave the Sands

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

Radiant, Archangel

Flying, vigilance
Radiant gets +1/+1 for each other creature on the battlefield with flying.

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.)

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.)

Fencing Ace

Double strike (This creature deals both first-strike and regular combat damage.)

Grasp of the Hieromancer

Enchant creature
Enchanted creature gets +1/+1 and has "Whenever this creature attacks, tap target creature defending player controls."

Seraph of the Sword

Flying
Prevent all combat damage that would be dealt to this creature.

Suntail Hawk

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}.

Aven Brigadier

Flying
Other Bird creatures get +1/+1.
Other Soldier creatures get +1/+1.

Boros Elite

Battalion — Whenever this creature and at least two other creatures attack, this creature gets +2/+2 until end of turn.

Plains

Falconer Adept

Whenever this creature attacks, create a 1/1 white Bird creature token with flying that's tapped and attacking.

Makeshift Battalion

Battalion — Whenever this creature and at least two other creatures attack, put a +1/+1 counter on this creature.

Sol Ring

Grappling Hook

Equipped creature has double strike.
Whenever equipped creature attacks, you may have target creature block it this turn if able.
Equip {4}

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.)

Aven Squire

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

Daru Encampment

{T}: Add {C}.
{W}, {T}: Target Soldier creature gets +1/+1 until end of turn.

Emeria, the Sky Ruin

This land enters tapped.
At the beginning of your upkeep, if you control seven or more Plains, you may return target creature card from your graveyard to the battlefield.
{T}: Add {W}.

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.

Sandstone Bridge

This land enters tapped.
When this land enters, target creature gets +1/+1 and gains vigilance until end of turn.
{T}: Add {W}.