Ghostly Prison

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Basandra, Battle Seraph

Flying
Players can't cast spells during combat.
{R}: Target creature attacks this turn if able.

Sol Ring

Vanquish the Horde

This spell costs {1} less to cast for each creature on the battlefield.
Destroy all creatures.

Cut a Deal

Each opponent draws a card, then you draw a card for each opponent who drew a card this way.

Assemble the Legion

At the beginning of your upkeep, put a muster counter on Assemble the Legion. Then create a 1/1 red and white Soldier creature token with haste for each muster counter on Assemble the Legion.

Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Hixus, Prison Warden

Flash (You may cast this spell any time you could cast an instant.)
Whenever a creature deals combat damage to you, if Hixus, Prison Warden entered this turn, exile that creature until Hixus leaves the battlefield. (That creature returns under its owner's control.)

Monologue Tax

Whenever an opponent casts their second spell each turn, you create a Treasure token.

Secret Rendezvous

You and target opponent each draw three cards.

Talisman of Conviction

{T}: Add {C}.
{T}: Add {R} or {W}. Talisman of Conviction deals 1 damage to you.

Marble Diamond

Marble Diamond enters tapped.
{T}: Add {W}.

Boros Signet

Fire Diamond

Fire Diamond enters tapped.
{T}: Add {R}.

Curse of Opulence

Enchant player
Whenever enchanted player is attacked, create a Gold token. Each opponent attacking that player does the same. (A Gold token is an artifact with "Sacrifice this artifact: Add one mana of any color.")

Palace Jailer

When Palace Jailer enters, you become the monarch.
When Palace Jailer enters, exile target creature an opponent controls until an opponent becomes the monarch.

Baird, Steward of Argive

Vigilance
Creatures can't attack you or planeswalkers you control unless their controller pays {1} for each of those creatures.

Smothering Tithe

Whenever an opponent draws a card, that player may pay {2}. If the player doesn't, you create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")