Marauding Blight-Priest

Whenever you gain life, each opponent loses 1 life.

Suffocating Fumes

Creatures your opponents control get -1/-1 until end of turn.
Cycling {2} ({2}, Discard this card: Draw a card.)

Swamp

Cast Down

Vampire Spawn

When this creature enters, each opponent loses 2 life and you gain 2 life.

Defile

Target creature gets -1/-1 until end of turn for each Swamp you control.

Wedding Invitation

When Wedding Invitation enters, draw a card.
{T}, Sacrifice Wedding Invitation: Target creature can't be blocked this turn. If it's a Vampire, it also gains lifelink until end of turn.

Gift of Fangs

Enchant creature
Enchanted creature gets +2/+2 as long as it's a Vampire. Otherwise, it gets -2/-2.

Vampire's Kiss

Target player loses 2 life and you gain 2 life. Create two Blood tokens. (They're artifacts with "{1}, {T}, Discard a card, Sacrifice this artifact: Draw a card.")

Sign in Blood

Target player draws two cards and loses 2 life.

Alms of the Vein

Target opponent loses 3 life and you gain 3 life.
Madness {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.)

Ichor Wellspring

When Ichor Wellspring enters or is put into a graveyard from the battlefield, draw a card.

Blood Fountain

When Blood Fountain enters, create a Blood token. (It's an artifact with "{1}, {T}, Discard a card, Sacrifice this artifact: Draw a card.")
{3}{B}, {T}, Sacrifice Blood Fountain: Return up to two target creature cards from your graveyard to your hand.

Vampire Sovereign

Flying
When Vampire Sovereign enters, target opponent loses 3 life and you gain 3 life.