Cavern of Souls

As Cavern of Souls enters the battlefield, choose a creature type. {T}: Add {1} to your mana pool. {T}: Add one mana of any color to your mana pool. Spend this mana only to cast a creature spell of the chosen type, and that spell can't be countered.

City of Traitors

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

Thorn of Amethyst

Noncreature spells cost {1} more to play.

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.

Umezawa's Jitte

Whenever equipped creature deals combat damage, put two charge counters on Umezawa's Jitte. Remove a charge counter from Umezawa's Jitte: Choose one — Equipped creature gets +2/+2 until end of turn; or target creature gets -1/-1 until end of turn; or you gain 2 life. Equip {2}

Dismember

({B/P} can be paid with either {B} or 2 life.) Target creature gets -5/-5 until end of turn.

Karakas

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

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.

Precursor Golem

When Precursor Golem enters the battlefield, put two 3/3 colorless Golem artifact creature tokens onto the battlefield. Whenever a player casts an instant or sorcery spell that targets only a single Golem, that player copies that spell for each other Golem that spell could target. Each copy targets a different one of those Golems.

Faerie Macabre

Flying Discard Faerie Macabre: Remove up to two target cards in graveyards from the game.

Pithing Needle

As Pithing Needle comes into play, name a card. Activated abilities of sources with the chosen name can't be played unless they're mana abilities.

Caves of Koilos

{T}: Add {1} to your mana pool. {T}: Add {W} or {B} to your mana pool. Caves of Koilos deals 1 damage to you.

Endless One

Bearer of Silence

Eldrazi Displacer

Eldrazi Mimic

Endbringer

Reality Smasher

Thought-Knot Seer

Warping Wail

Ancient Tomb

Eye of Ugin

Wasteland