Mana Leak

Counter target spell unless its controller pays {3}.

Psychic Venom

Enchant land
Whenever enchanted land becomes tapped, Psychic Venom deals 2 damage to that land's controller.

Mountain

Exhaustion

Creatures and lands target opponent controls don't untap during their next untap step.

Sulfur Falls

Sulfur Falls enters tapped unless you control an Island or a Mountain.
{T}: Add {U} or {R}.

Mana Short

Tap all lands target player controls and that player loses all unspent mana.

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Manabarbs

Whenever a player taps a land for mana, Manabarbs deals 1 damage to that player.

Melek, Izzet Paragon

Play with the top card of your library revealed.
You may cast instant and sorcery spells from the top of your library.
Whenever you cast an instant or sorcery spell from your library, copy it. You may choose new targets for the copy.

Mana Vapors

Lands target player controls don't untap during their next untap step.

Counterspell

Cascade Bluffs

{T}: Add {C}.
{U/R}, {T}: Add {U}{U}, {U}{R}, or {R}{R}.

Stone Rain

Rishadan Port

Rhystic Study

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

Gulf Squid

When Gulf Squid enters, tap all lands target player controls.

Mystic Remora

Cumulative upkeep {1} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
Whenever an opponent casts a noncreature spell, you may draw a card unless that player pays {4}.

Island

Mana Web

Whenever a land an opponent controls is tapped for mana, tap all lands that player controls that could produce any type of mana that land could produce.

Citadel of Pain

At the beginning of each player's end step, Citadel of Pain deals X damage to that player, where X is the number of untapped lands they control.

Stormcarved Coast

Stormcarved Coast enters tapped unless you control two or more other lands.
{T}: Add {U} or {R}.

Ankh of Mishra

Whenever a land enters, Ankh of Mishra deals 2 damage to that land's controller.