Raise the Alarm

Create two 1/1 white Soldier creature tokens.

Plains

Idyllic Grange

({T}: Add {W}.)
Idyllic Grange enters tapped unless you control three or more other Plains.
When Idyllic Grange enters untapped, put a +1/+1 counter on target creature you control.

Mana Tithe

Counter target spell unless its controller pays {1}.

Hidden Courtyard

Hidden Courtyard enters tapped.
{T}: Add {W}.
{4}{W}, {T}, Sacrifice Hidden Courtyard: Discover 4. Activate only as a sorcery. (Exile cards from the top of your library until you exile a nonland card with mana value 4 or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)

Pacifism

Enchant creature
Enchanted creature can't attack or block.

Inside Source

When Inside Source enters, create a 2/2 white and blue Detective creature token.
{3}, {T}: Target Detective you control gets +2/+0 and gains vigilance until end of turn. Activate only as a sorcery.

Gideon's Reproach

Gideon's Reproach deals 4 damage to target attacking or blocking creature.

Adaptive Gemguard

Tap two untapped artifacts and/or creatures you control: Put a +1/+1 counter on Adaptive Gemguard. Activate only as a sorcery.

Attended Knight

First strike
When Attended Knight enters, create a 1/1 white Soldier creature token.

Impassioned Orator

Whenever another creature you control enters, you gain 1 life.

Steadfast Unicorn

{3}{W}: Creatures you control get +1/+1 and gain vigilance until end of turn. Activate only during your turn. (Attacking doesn't cause them to tap.)

Aven Squire

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

Flaming Fist Officer

Whenever another creature you control leaves the battlefield, put a +1/+1 counter on Flaming Fist Officer.

Sandstone Bridge

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

Sea Gate Banneret

{4}{W}: Creatures you control get +1/+1 until end of turn.

Oppressive Rays

Enchant creature
Enchanted creature can't attack or block unless its controller pays {3}.
Activated abilities of enchanted creature cost {3} more to activate.

Eagles of the North

Flying
When Eagles of the North enters, creatures you control get +1/+0 and gain first strike until end of turn.
Plainscycling {1} ({1}, Discard this card: Search your library for a Plains card, reveal it, put it into your hand, then shuffle.)

Shoulder to Shoulder

Support 2. (Put a +1/+1 counter on each of up to two target creatures.)
Draw a card.

Revoke Existence

Selfless Cathar

{1}{W}, Sacrifice Selfless Cathar: Creatures you control get +1/+1 until end of turn.

Prowling Felidar

Vigilance
Landfall — Whenever a land you control enters, put a +1/+1 counter on Prowling Felidar.