Pestilence Rats

Pestilence Rats's power is equal to the number of other Rats on the battlefield. (For example, as long as there are two other Rats on the battlefield, Pestilence Rats's power and toughness are 2/3.)

Terror

Destroy target nonartifact, nonblack creature. It can't be regenerated.

Bog Rats

Strip Mine

{T}: Add {C}.
{T}, Sacrifice Strip Mine: Destroy target land.

Mishra's Factory

{T}: Add {C}.
{1}: Mishra's Factory becomes a 2/2 Assembly-Worker artifact creature until end of turn. It's still a land.
{T}: Target Assembly-Worker creature gets +1/+1 until end of turn.

Hymn to Tourach

Target player discards two cards at random.

Crypt Rats

{X}: Crypt Rats deals X damage to each creature and each player. Spend only black mana on X.

Black Lotus

{T}, Sacrifice Black Lotus: Add three mana of any one color.

Swamp

Raise Dead

Return target creature card from your graveyard to your hand.

Mind Twist

Target player discards X cards at random.

Dark Ritual

Paralyze

Enchant creature
When Paralyze enters, tap enchanted creature.
Enchanted creature doesn't untap during its controller's untap step.
At the beginning of the upkeep of enchanted creature's controller, that player may pay {4}. If the player does, untap the creature.

Plague Rats

Plague Rats's power and toughness are each equal to the number of creatures named Plague Rats on the battlefield.

Fear

Enchant creature (Target a creature as you cast this. This card enters attached to that creature.)
Enchanted creature has fear. (It can't be blocked except by artifact creatures and/or black creatures.)