City of Traitors

When you play another land, sacrifice City of Traitors.
{T}: Add {C}{C}.

Thought-Knot Seer

({C} represents colorless mana.)
When Thought-Knot Seer enters, target opponent reveals their hand. You choose a nonland card from it and exile that card.
When Thought-Knot Seer leaves the battlefield, target opponent draws a card.

Karakas

{T}: Add {W}.
{T}: Return target legendary creature to its owner's hand.

Flooded Strand

{T}, Pay 1 life, Sacrifice Flooded Strand: Search your library for a Plains or Island card, put it onto the battlefield, then shuffle.

Thalia, Heretic Cathar

First strike
Creatures and nonbasic lands your opponents control enter tapped.

Chalice of the Void

Chalice of the Void enters with X charge counters on it.
Whenever a player casts a spell with mana value equal to the number of charge counters on Chalice of the Void, counter that spell.

Lotus Petal

{T}, Sacrifice Lotus Petal: Add one mana of any color.

Crystal Vein

{T}: Add {C}.
{T}, Sacrifice Crystal Vein: Add {C}{C}.

Archon of Emeria

Flying
Each player can't cast more than one spell each turn.
Nonbasic lands your opponents control enter tapped.

Lodestone Golem

Nonartifact spells cost {1} more to cast.

Thalia, Guardian of Thraben

First strike
Noncreature spells cost {1} more to cast.

Thorn of Amethyst

Noncreature spells cost {1} more to cast.

Wasteland

{T}: Add {C}.
{T}, Sacrifice Wasteland: Destroy target nonbasic land.

Generous Gift

Destroy target permanent. Its controller creates a 3/3 green Elephant creature token.

Eldrazi Temple

{T}: Add {C}.
{T}: Add {C}{C}. Spend this mana only to cast colorless Eldrazi spells or activate abilities of colorless Eldrazi.

Ancient Tomb

{T}: Add {C}{C}. Ancient Tomb deals 2 damage to you.

Reality Smasher

({C} represents colorless mana.)
Trample, haste
Whenever Reality Smasher becomes the target of a spell an opponent controls, counter that spell unless its controller discards a card.