Manabarbs

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

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.

Seismic Spike

Darksteel Citadel

Chromatic Lantern

Lands you control have "{T}: Add one mana of any color."
{T}: Add one mana of any color.

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Orcish Settlers

{X}{X}{R}, {T}, Sacrifice this creature: Destroy X target lands.

Obliterate

This spell can't be countered.
Destroy all artifacts, creatures, and lands. They can't be regenerated.

Ruination

Dwarven Miner

{2}{R}, {T}: Destroy target nonbasic land.

Armageddon

Wasteland

{T}: Add {C}.
{T}, Sacrifice this land: Destroy target nonbasic land.

Darksteel Ingot

Indestructible (Effects that say "destroy" don't destroy this artifact.)
{T}: Add one mana of any color.

Counterspell

Command Tower

{T}: Add one mana of any color in your commander's color identity.

Detritivore

Detritivore's power and toughness are each equal to the number of nonbasic land cards in your opponents' graveyards.
Suspend X—{X}{3}{R}. X can't be 0. (Rather than cast this card from your hand, you may pay {X}{3}{R} and exile it with X time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost. It has haste.)
Whenever a time counter is removed from this card while it's exiled, destroy target nonbasic land.

Price of Glory

Whenever a player taps a land for mana, if it's not that player's turn, destroy that land.

Winter Orb

As long as this artifact is untapped, players can't untap more than one land during their untap steps.

Numot, the Devastator

Flying
Whenever Numot deals combat damage to a player, you may pay {2}{R}. If you do, destroy up to two target lands.