Elvish Spirit Guide

If Elvish Spirit Guide is in your hand, you may remove it from the game to add {G} to your mana pool. Play this ability as an interrupt.

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.

Spirit of the Labyrinth

Each player can't draw more than one card each turn.

Containment Priest

Flash If a nontoken creature would enter the battlefield and it wasn't cast, exile it instead.

Thalia, Guardian of Thraben

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

Stony Silence

Activated abilities of artifacts can't be activated.

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.

Simian Spirit Guide

Remove Simian Spirit Guide in your hand from the game: Add {R} to your mana pool.

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}

Mana Crypt

At the beginning of your upkeep, flip a coin. If you lose the flip, Mana Crypt deals 3 damage to you. {T}: Add {2} to your mana pool.

Karakas

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

Kataki, War's Wage

All artifacts have "At the beginning of your upkeep, sacrifice this artifact unless you pay {1}."

Lotus Petal

Sacrifice Lotus Petal: Add one mana of any color to your mana pool. Play this ability as a mana source.

Mox Ruby

Add 1 red mana to your mana pool. Tapping this artifact can be played as an interrupt.

Mox Pearl

Add 1 white mana to your mana pool. Tapping this artifact can be played as an interrupt.

Black Lotus

Adds 3 mana of any single color of your choice to your mana pool, then is discarded. Tapping this artifact can be played as an interrupt.

Ghost Quarter

Horizon Canopy

Strip Mine

Wasteland

Thalia, Heretic Cathar

Plains

({T}: Add {W}.)