Sign in Blood

Target player draws two cards and loses 2 life.

Gravedigger

When this creature enters, you may return target creature card from your graveyard to your hand.

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.

Dead Weight

Enchant creature
Enchanted creature gets -2/-2.

Mind Rot

Nightmare

Flying (This creature can't be blocked except by creatures with flying or reach.)
Nightmare's power and toughness are each equal to the number of Swamps you control.

Vampire Nighthawk

Flying
Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Doom Blade

Vampire of the Dire Moon

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Bloodrite Invoker

{8}: Target player loses 3 life and you gain 3 life.

Swamp

Bloodgift Demon

Flying
At the beginning of your upkeep, target player draws a card and loses 1 life.