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.

Blinkmoth Nexus

{T}: Add {1} to your mana pool. {1}: Blinkmoth Nexus becomes a 1/1 Blinkmoth artifact creature with flying until end of turn. It's still a land. {1}, {T}: Target Blinkmoth creature gets +1/+1 until end of turn.

Spellskite

{U/P}: Change a target of target spell or ability to Spellskite. ({U/P} can be paid with either {U} or 2 life.)

Simian Spirit Guide

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

Urborg, Tomb of Yawgmoth

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

Mutavault

{T}: Add {1} to your mana pool. {1}: Mutavault becomes a 2/2 creature with all creature types until end of turn. It's still a land.

Dismember

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

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.

Ratchet Bomb

{T}: Put a charge counter on Ratchet Bomb. {T}, Sacrifice Ratchet Bomb: Destroy each nonland permanent with converted mana cost equal to the number of charge counters on Ratchet Bomb.

Endless One

Ghost Quarter

Eldrazi Mimic

Matter Reshaper

Reality Smasher

Thought-Knot Seer

Warping Wail

Wastes

Eye of Ugin