Plains

Haazda Snare Squad

Whenever Haazda Snare Squad attacks, you may pay {W}. If you do, tap target creature an opponent controls.

Lavinia of the Tenth

Protection from red
When Lavinia of the Tenth enters, detain each nonland permanent your opponents control with mana value 4 or less. (Until your next turn, those permanents can't attack or block and their activated abilities can't be activated.)

Arrest

Enchant creature
Enchanted creature can't attack or block, and its activated abilities can't be activated.

Wind Drake

Lyev Decree

Detain up to two target creatures your opponents control. (Until your next turn, those creatures can't attack or block and their activated abilities can't be activated.)

Island

Soulsworn Spirit

Soulsworn Spirit can't be blocked.
When Soulsworn Spirit enters, detain target creature an opponent controls. (Until your next turn, that creature can't attack or block and its activated abilities can't be activated.)

Azorius Cluestone

{T}: Add {W} or {U}.
{W}{U}, {T}, Sacrifice Azorius Cluestone: Draw a card.

Restore the Peace

Return each creature that dealt damage this turn to its owner's hand.

Ascended Lawmage

Flying
Hexproof (This creature can't be the target of spells or abilities your opponents control.)

Azorius Arrester

When Azorius Arrester enters, detain target creature an opponent controls. (Until your next turn, that creature can't attack or block and its activated abilities can't be activated.)

Martial Law

At the beginning of your upkeep, detain target creature an opponent controls. (Until your next turn, that creature can't attack or block and its activated abilities can't be activated.)

Serve

Target creature gets -6/-0 until end of turn.
Fuse (You may cast one or both halves of this card from your hand.)

Protect

Target creature gets +2/+4 until end of turn.
Fuse (You may cast one or both halves of this card from your hand.)

Protect // Serve

Azorius Justiciar

When Azorius Justiciar enters, detain up to two target creatures your opponents control. (Until your next turn, those creatures can't attack or block and their activated abilities can't be activated.)

Azorius Guildgate

Azorius Guildgate enters tapped.
{T}: Add {W} or {U}.

Lyev Skyknight

Flying
When Lyev Skyknight enters, detain target nonland permanent an opponent controls. (Until your next turn, that permanent can't attack or block and its activated abilities can't be activated.)

Righteous Charge

Creatures you control get +2/+2 until end of turn.

Silvercoat Lion

Stealer of Secrets

Whenever Stealer of Secrets deals combat damage to a player, draw a card.

Avenging Arrow

Destroy target creature that dealt damage this turn.

Sunspire Gatekeepers

When Sunspire Gatekeepers enters, if you control two or more Gates, create a 2/2 white Knight creature token with vigilance.

Jelenn Sphinx

Flying, vigilance
Whenever Jelenn Sphinx attacks, other attacking creatures get +1/+1 until end of turn.