Insidious Bookworms

When Insidious Bookworms dies, you may pay {1}{B}. If you do, target player discards a card at random.

Krovikan Sorcerer

{T}, Discard a nonblack card: Draw a card.
{T}, Discard a black card: Draw two cards, then discard one of them.

Counterspell

Underground River

{T}: Add {C}.
{T}: Add {U} or {B}. Underground River deals 1 damage to you.

Skeleton Ship

When you control no Islands, sacrifice Skeleton Ship.
{T}: Put a -1/-1 counter on target creature.

Sengir Autocrat

When Sengir Autocrat enters, create three 0/1 black Serf creature tokens.
When Sengir Autocrat leaves the battlefield, exile all Serf tokens.

Brine Shaman

{T}, Sacrifice a creature: Target creature gets +2/+2 until end of turn.
{1}{U}{U}, Sacrifice a creature: Counter target creature spell.

Phantasmal Fiend

{B}: Phantasmal Fiend gets +1/-1 until end of turn.
{1}{U}: Switch Phantasmal Fiend's power and toughness until end of turn.

Abyssal Specter

Flying
Whenever Abyssal Specter deals damage to a player, that player discards a card.

Power Sink

Counter target spell unless its controller pays {X}. If that player doesn't, they tap all lands with mana abilities they control and lose all unspent mana.

Castle Sengir

{T}: Add {C}.
{1}, {T}: Add {B}.
{2}, {T}: Add {U} or {R}.

River Delta

River Delta doesn't untap during your untap step if it has a depletion counter on it.
At the beginning of your upkeep, remove a depletion counter from River Delta.
{T}: Add {U} or {B}. Put a depletion counter on River Delta.

Dark Banishing

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

Zuran Enchanter

{2}{B}, {T}: Target player discards a card. Activate only during your turn.

Essence Vortex

Destroy target creature unless its controller pays life equal to its toughness. A creature destroyed this way can't be regenerated.

Stromgald Cabal

{T}, Pay 1 life: Counter target white spell.

Stromgald Spy

Whenever Stromgald Spy attacks and isn't blocked, you may have defending player play with their hand revealed for as long as Stromgald Spy remains on the battlefield. If you do, Stromgald Spy assigns no combat damage this turn.

Wall of Kelp

Defender (This creature can't attack.)
{U}{U}, {T}: Create a 0/1 blue Plant Wall creature token with defender named Kelp.

Snow-Covered Swamp

Kjeldoran Dead

When Kjeldoran Dead enters, sacrifice a creature.
{B}: Regenerate Kjeldoran Dead.

Viscerid Drone

{T}, Sacrifice a creature and a Swamp: Destroy target nonartifact creature. It can't be regenerated.
{T}, Sacrifice a creature and a snow Swamp: Destroy target creature. It can't be regenerated.

Thawing Glaciers

Thawing Glaciers enters tapped.
{1}, {T}: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle. Return Thawing Glaciers to its owner's hand at the beginning of the next cleanup step.

Diabolic Vision

Look at the top five cards of your library. Put one of them into your hand and the rest on top of your library in any order.

Ritual of the Machine

As an additional cost to cast this spell, sacrifice a creature.
Gain control of target nonartifact, nonblack creature.

Soldevi Adnate

{T}, Sacrifice a black or artifact creature: Add an amount of {B} equal to the sacrificed creature's mana value.