Swamp

Altar of the Brood

Whenever another permanent enters the battlefield under your control, each opponent mills a card.

Grasp of Darkness

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

Dark Ritual

Heartless Summoning

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

Go for the Throat

Fatal Push

Destroy target creature if it has mana value 2 or less.
Revolt — Destroy that creature if it has mana value 4 or less instead if a permanent you controlled left the battlefield this turn.

Myr Retriever

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

Thoughtseize

Target player reveals their hand. You choose a nonland card from it. That player discards that card. You lose 2 life.