Omnath, Locus of All

If you would lose unspent mana, that mana becomes black instead.
At the beginning of your first main phase, look at the top card of your library. You may reveal that card if it has three or more colored mana symbols in its mana cost. If you do, add three mana in any combination of its colors and put it into your hand. If you don't reveal it, put it into your hand.

Underworld Dreams

Whenever an opponent draws a card, this enchantment deals 1 damage to that player.

Dread Shade

{B}: This creature gets +1/+1 until end of turn.

Phyrexian Etchings

Cumulative upkeep {B} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
At the beginning of your end step, draw a card for each age counter on this enchantment.
When this enchantment is put into a graveyard from the battlefield, you lose 2 life for each age counter on it.

Necropotence

Skip your draw step.
Whenever you discard a card, exile that card from your graveyard.
Pay 1 life: Exile the top card of your library face down. Put that card into your hand at the beginning of your next end step.

Gravestorm

At the beginning of your upkeep, target opponent may exile a card from their graveyard. If that player doesn't, you may draw a card.