Command Tower

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

Rakdos, the Muscle

Flying, trample
Whenever you sacrifice another creature, exile cards equal to its mana value from the top of target player's library. Until your next end step, you may play those cards, and mana of any type can be spent to cast those spells.
Sacrifice another creature: Rakdos, the Muscle gains indestructible until end of turn. Tap it. Activate only once each turn.

Rising of the Day

Creatures you control have haste.
Legendary creatures you control get +1/+0.

Pitiless Plunderer

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

Reassembling Skeleton

{1}{B}: Return this card from your graveyard to the battlefield tapped.

Malakir Mire

Malakir Mire enters tapped.
{T}: Add {B}.

Malakir Rebirth

Choose target creature. You lose 2 life. Until end of turn, that creature gains "When this creature dies, return it to the battlefield tapped under its owner's control."

Malakir Rebirth // Malakir Mire

Ryusei, the Falling Star

Flying
When Ryusei, the Falling Star dies, it deals 5 damage to each creature without flying.

Pestilence Demon

Flying
{B}: Pestilence Demon deals 1 damage to each creature and each player.

Commander's Sphere

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

Costly Plunder

As an additional cost to cast this spell, sacrifice an artifact or creature.
Draw two cards.

Sol Ring

Defiler of Flesh

Menace
As an additional cost to cast black permanent spells, you may pay 2 life. Those spells cost {B} less to cast if you paid life this way. This effect reduces only the amount of black mana you pay.
Whenever you cast a black permanent spell, target creature you control gets +1/+1 and gains menace until end of turn.

Unhallowed Pact

Enchant creature
When enchanted creature dies, return that card to the battlefield under your control.

Evolving Wilds

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.