Charcoal Diamond

This artifact enters tapped.
{T}: Add {B}.

Songs of the Damned

Add {B} for each creature card in your graveyard.

Commander's Sphere

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

Bubbling Muck

Until end of turn, whenever a player taps a Swamp for mana, that player adds an additional {B}.

Shirei, Shizo's Caretaker

Whenever a creature with power 1 or less is put into your graveyard from the battlefield, you may return that card to the battlefield at the beginning of the next end step if Shirei is still on the battlefield.

Arcane Signet

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

Dark Ritual

Snuff Out

If you control a Swamp, you may pay 4 life rather than pay this spell's mana cost.
Destroy target nonblack creature. It can't be regenerated.