Myr Retriever

When Myr Retriever dies, return another target artifact card from your graveyard to your hand.

Wight of Precinct Six

Wight of Precinct Six gets +1/+1 for each creature card in your opponents' graveyards.

Swamp

Grinding Station

{T}, Sacrifice an artifact: Target player mills three cards.
Whenever an artifact enters, you may untap Grinding Station.

Gatekeeper of Malakir

Kicker {B} (You may pay an additional {B} as you cast this spell.)
When this creature enters, if it was kicked, target player sacrifices a creature of their choice.

Altar of the Brood

Whenever another permanent you control enters, each opponent mills a card.

Grasp of Darkness

Target creature gets -4/-4 until end of turn.

Go for the Throat

Beseech the Queen

({2/B} can be paid with any two mana or with {B}. This card's mana value is 6.)
Search your library for a card with mana value less than or equal to the number of lands you control, reveal it, put it into your hand, then shuffle.

Heartless Summoning

Creature spells you cast cost {2} less to cast.
Creatures you control get -1/-1.