Braids, Cabal Minion

At the beginning of each player's upkeep, that player sacrifices an artifact, creature, or land of their choice.

Bojuka Bog

This land enters tapped.
When this land enters, exile target player's graveyard.
{T}: Add {B}.

Whenever another creature you control dies, create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Black spells you cast cost {1} less to cast.

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

Whenever this creature or another creature dies, target player loses 1 life and you gain 1 life.

As an additional cost to cast this spell, sacrifice a creature.
Add {B}{B}{B}{B}.

Destroy target creature or enchantment an opponent controls. You lose life equal to that permanent's mana value.