Read the Bones

Scry 2, then draw two cards. You lose 2 life. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Charcoal Diamond

Charcoal Diamond enters tapped.
{T}: Add {B}.

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Everflowing Chalice

Multikicker {2} (You may pay an additional {2} any number of times as you cast this spell.)
Everflowing Chalice enters with a charge counter on it for each time it was kicked.
{T}: Add {C} for each charge counter on Everflowing Chalice.

Sol Ring

Thought Vessel

You have no maximum hand size.
{T}: Add {C}.

Diabolic Edict

Target player sacrifices a creature of their choice.

Diabolic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Dark Ritual

Hedron Archive

{T}: Add {C}{C}.
{2}, {T}, Sacrifice this artifact: Draw two cards.

Worn Powerstone

Worn Powerstone enters tapped.
{T}: Add {C}{C}.

Sign in Blood

Target player draws two cards and loses 2 life.

Fellwar Stone

{T}: Add one mana of any color that a land an opponent controls could produce.

Razaketh's Rite

Search your library for a card, put that card into your hand, then shuffle.
Cycling {B} ({B}, Discard this card: Draw a card.)

K'rrik, Son of Yawgmoth

({B/P} can be paid with either {B} or 2 life.)
Lifelink
For each {B} in a cost, you may pay 2 life rather than pay that mana.
Whenever you cast a black spell, put a +1/+1 counter on K'rrik, Son of Yawgmoth.

Basalt Monolith

Basalt Monolith doesn't untap during your untap step.
{T}: Add {C}{C}{C}.
{3}: Untap Basalt Monolith.

Decanter of Endless Water

You have no maximum hand size.
{T}: Add one mana of any color.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Thran Dynamo

Syphon Mind

Each other player discards a card. You draw a card for each card discarded this way.

Demon's Horn

Whenever a player casts a black spell, you may gain 1 life.

Essence Harvest

Target player loses X life and you gain X life, where X is the greatest power among creatures you control.

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.