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.

Cloudpost

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

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.

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.

Thran Dynamo

{T}: Add three colorless mana to your mana pool.

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.

Voltaic Key

{1}, {T}: Untap target artifact.

Hedron Archive

Ulamog, the Ceaseless Hunger

Endbringer

Kozilek, the Great Distortion

Spatial Contortion

Thought-Knot Seer

Ancient Tomb

Eye of Ugin

Emrakul, the Promised End

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.