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.

Dark Depths

Dark Depths comes into play with ten ice counters on it. {3}: Remove an ice counter from Dark Depths. When Dark Depths has no ice counters on it, sacrifice it. If you do, put an indestructible legendary 20/20 black Avatar creature token with flying named Marit Lage into play.

Into the North

Search your library for a snow land card and put it into play tapped. Then shuffle your library.

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.

Snow-Covered Forest

{T}: Add {G} to your mana pool.

Snow-Covered Swamp

{T}: Add {B} to your mana pool.

Sylvan Safekeeper

Sacrifice a land: Target creature you control can't be the target of spells or abilities this turn.

Thorn of Amethyst

Noncreature spells cost {1} more to play.

Urborg, Tomb of Yawgmoth

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

Lotus Petal

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

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.

Thoughtseize

Target player reveals his or her hand. You choose a nonland card from it. That player discards that card. You lose 2 life.

Bayou

Counts as both swamp and forest and is affected by spells that affect either. Tap to add either {B} or {G} to your mana pool.

Crop Rotation

At the time you play Crop Rotation, sacrifice a land. Search your library for a land card and put that land into play. Shuffle your library afterwards.

Bojuka Bog

Bojuka Bog enters the battlefield tapped. When Bojuka Bog enters the battlefield, exile all cards from target player's graveyard. {T}: Add {B} to your mana pool.

Sejiri Steppe

Sejiri Steppe enters the battlefield tapped. When Sejiri Steppe enters the battlefield, target creature you control gains protection from the color of your choice until end of turn. {T}: Add {W} to your mana pool.

Vampire Hexmage

First strike Sacrifice Vampire Hexmage: Remove all counters from target permanent.

Expedition Map

{2}, {T}, Sacrifice Expedition Map: Search your library for a land card, reveal it, and put it into your hand. Then shuffle your library.

Verdant Catacombs

Sylvan Scrying

Ghost Quarter

Duress

Target opponent reveals their hand. You choose a noncreature, nonland card from it. That player discards that card.