Pygmy Allosaurus

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)

Demonic Hordes

{T}: Destroy target land.
At the beginning of your upkeep, unless you pay {B}{B}{B}, tap this creature and sacrifice a land of an opponent's choice.

Blight

Enchant land
When enchanted land becomes tapped, destroy it.

Bog Wraith

Black Lotus

{T}, Sacrifice this artifact: Add three mana of any one color.

Swamp

Bayou

Mox Emerald

Moor Fiend

Mox Jet

Lost Soul

Forest

Evil Presence

Cyclopean Tomb

{2}, {T}: Put a mire counter on target non-Swamp land. That land is a Swamp for as long as it has a mire counter on it. Activate only during your upkeep.
When this artifact is put into a graveyard from the battlefield, at the beginning of each of your upkeeps for the rest of the game, remove all mire counters from a land that a mire counter was put onto with this artifact but that a mire counter has not been removed from with this artifact.

Sinkhole

Ice Storm

Dark Ritual

Icequake

Destroy target land. If that land was a snow land, Icequake deals 1 damage to that land's controller.

Fastbond

You may play any number of lands on each of your turns.
Whenever you play a land, if it wasn't the first land you played this turn, this enchantment deals 1 damage to you.