Path of Ancestry

Path of Ancestry enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Pearl Medallion

White spells you cast cost {1} less to cast.

Helm of Awakening

Foundry Inspector

Artifact spells you cast cost {1} less to cast.

Sunscape Familiar

Defender (This creature can't attack.)
Green spells and blue spells you cast cost {1} less to cast.

Urza's Incubator

As Urza's Incubator enters, choose a creature type.
Creature spells of the chosen type cost {2} less to cast.

Mistform Warchief

Creature spells you cast that share a creature type with Mistform Warchief cost {1} less to cast.
{T}: Mistform Warchief becomes the creature type of your choice until end of turn.

Centaur Omenreader

As long as Centaur Omenreader is tapped, creature spells you cast cost {2} less to cast.

Thunderscape Familiar

First strike
Black spells and green spells you cast cost {1} less to cast.

Living Wish

You may reveal a creature or land card you own from outside the game and put it into your hand. Exile Living Wish.

Heartstone

Activated abilities of creatures cost {1} less to activate. This effect can't reduce the mana in that cost to less than one mana.

City of Brass

Whenever City of Brass becomes tapped, it deals 1 damage to you.
{T}: Add one mana of any color.

Starnheim Courser

Flying
Artifact and enchantment spells you cast cost {1} less to cast.

Stormscape Familiar

Flying
White spells and black spells you cast cost {1} less to cast.

Enthusiastic Mechanaut

Flying
Artifact spells you cast cost {1} less to cast.

Emerald Medallion

Green spells you cast cost {1} less to cast.

Watcher of the Spheres

Flying
Creature spells with flying you cast cost {1} less to cast.
Whenever another creature you control with flying enters, Watcher of the Spheres gets +1/+1 until end of turn.

Cloud Key

As Cloud Key enters, choose artifact, creature, enchantment, instant, or sorcery.
Spells you cast of the chosen type cost {1} less to cast.