City of Traitors

If you play any land, sacrifice City of Traitors. {T}: Add two colorless mana to your mana pool.

Ugin, the Spirit Dragon

+2: Ugin, the Spirit Dragon deals 3 damage to target creature or player. -X: Exile each permanent with converted mana cost X or less that's one or more colors. -10: You gain 7 life, draw seven cards, then put up to seven permanent cards from your hand onto the battlefield.

Trinisphere

As long as Trinisphere is untapped, each spell that would cost less than three mana to cast costs three mana to cast. (Additional mana in the cost may be paid with any color of mana or colorless mana. For example, a spell that would cost {1}{B} to cast costs {2}{B} to cast instead.)

Thespian's Stage

{T}: Add {1} to your mana pool. {2}, {T}: Thespian's Stage becomes a copy of target land and gains this ability.

Chalice of the Void

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

Urborg, Tomb of Yawgmoth

Each land is a Swamp in addition to its other land types.

Cloudpost

Cloudpost enters the battlefield tapped. {T}: Add {1} to your mana pool for each Locus on the battlefield.

All Is Dust

Each player sacrifices all colored permanents he or she controls.

Kozilek, Butcher of Truth

When you cast Kozilek, Butcher of Truth, draw four cards. Annihilator 4 (Whenever this creature attacks, defending player sacrifices four permanents.) When Kozilek is put into a graveyard from anywhere, its owner shuffles his or her graveyard into his or her library.

Eldrazi Temple

{T}: Add {1} to your mana pool. {T}: Add {2} to your mana pool. Spend this mana only to cast colorless Eldrazi spells or activate abilities of colorless Eldrazi.

Glimmerpost

When Glimmerpost enters the battlefield, you gain 1 life for each Locus on the battlefield. {T}: Add {1} to your mana pool.

Wurmcoil Engine

Deathtouch, lifelink When Wurmcoil Engine is put into a graveyard from the battlefield, put a 3/3 colorless Wurm artifact creature token with deathtouch and a 3/3 colorless Wurm artifact creature token with lifelink onto the battlefield.

Vesuva

As Vesuva comes into play, you may choose a land in play. If you do, Vesuva comes into play tapped as a copy of the chosen land.

Grim Monolith

Grim Monolith does not untap during your untap phase. {4}: Untap Grim Monolith. {T}: Add three colorless mana to your mana pool. Play this ability as a mana source.

Ulamog, the Ceaseless Hunger

Kozilek, the Great Distortion

Thought-Knot Seer

Warping Wail

Ancient Tomb

Eye of Ugin

Emrakul, the Promised End

Walking Ballista

Sorcerous Spyglass

As Sorcerous Spyglass enters the battlefield, look at an opponent's hand, then choose any card name. Activated abilities of sources with the chosen name can't be activated unless they're mana abilities.