Howling Banshee

Flying
When Howling Banshee enters, each player loses 3 life.

Ravenous Rats

When Ravenous Rats enters, target opponent discards a card.

Drudge Skeletons

{B}: Regenerate Drudge Skeletons. (The next time this creature would be destroyed this turn, instead tap it, remove it from combat, and heal all damage on it.)

Phyrexian Rager

When Phyrexian Rager enters, you draw a card and you lose 1 life.

Liliana Vess

+1: Target player discards a card.
−2: Search your library for a card, then shuffle and put that card on top.
−8: Put all creature cards from all graveyards onto the battlefield under your control.

Corrupt

Corrupt deals damage to any target equal to the number of Swamps you control. You gain life equal to the damage dealt this way.

Rise from the Grave

Put target creature card from a graveyard onto the battlefield under your control. That creature is a black Zombie in addition to its other colors and types.

Wall of Bone

Defender (This creature can't attack.)
{B}: Regenerate Wall of Bone. (The next time this creature would be destroyed this turn, instead tap it, remove it from combat, and heal all damage on it.)

Keening Banshee

Flying
When Keening Banshee enters, target creature gets -2/-2 until end of turn.

Mutilate

All creatures get -1/-1 until end of turn for each Swamp you control.

Vicious Hunger

Vicious Hunger deals 2 damage to target creature and you gain 2 life.

Skeletal Vampire

Flying
When Skeletal Vampire enters, create two 1/1 black Bat creature tokens with flying.
{3}{B}{B}, Sacrifice a Bat: Create two 1/1 black Bat creature tokens with flying.
Sacrifice a Bat: Regenerate Skeletal Vampire.

Vampire Bats

Flying (This creature can't be blocked except by creatures with flying or reach.)
{B}: Vampire Bats gets +1/+0 until end of turn. Activate no more than twice each turn.

Ghost-Lit Stalker

{4}{B}, {T}: Target player discards two cards. Activate only as a sorcery.
Channel — {5}{B}{B}, Discard Ghost-Lit Stalker: Target player discards four cards. Activate only as a sorcery.

Urborg Syphon-Mage

{2}{B}, {T}, Discard a card: Each other player loses 2 life. You gain life equal to the life lost this way.

Sign in Blood

Target player draws two cards and loses 2 life.

Ichor Slick

Target creature gets -3/-3 until end of turn.
Cycling {2} ({2}, Discard this card: Draw a card.)
Madness {3}{B} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Polluted Mire

Polluted Mire enters tapped.
{T}: Add {B}.
Cycling {2} ({2}, Discard this card: Draw a card.)

Snuff Out

If you control a Swamp, you may pay 4 life rather than pay this spell's mana cost.
Destroy target nonblack creature. It can't be regenerated.

Twisted Abomination

{B}: Regenerate Twisted Abomination. (The next time this creature would be destroyed this turn, instead tap it, remove it from combat, and heal all damage on it.)
Swampcycling {2} ({2}, Discard this card: Search your library for a Swamp card, reveal it, put it into your hand, then shuffle.)

Hideous End

Destroy target nonblack creature. Its controller loses 2 life.

Genju of the Fens

Enchant Swamp
{2}: Until end of turn, enchanted Swamp becomes a 2/2 black Spirit creature with "{B}: This creature gets +1/+1 until end of turn." It's still a land.
When enchanted Swamp is put into a graveyard, you may return Genju of the Fens from your graveyard to your hand.

Bad Moon

Fleshbag Marauder

When Fleshbag Marauder enters, each player sacrifices a creature of their choice.

Deathgreeter

Whenever another creature dies, you may gain 1 life.

Faerie Macabre

Flying
Discard Faerie Macabre: Exile up to two target cards from graveyards.

Tendrils of Corruption

Tendrils of Corruption deals X damage to target creature and you gain X life, where X is the number of Swamps you control.

Enslave

Enchant creature
You control enchanted creature.
At the beginning of your upkeep, enchanted creature deals 1 damage to its owner.