Arcane Signet

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

Command Tower

Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

Rakdos Signet

Kefka, Ruler of Ruin

Flying
Whenever an opponent loses life during your turn, you draw that many cards.

Kefka, Court Mage

Whenever Kefka enters or attacks, each player discards a card. Then you draw a card for each card type among cards discarded this way.
{8}: Each opponent sacrifices a permanent of their choice. Transform Kefka. Activate only as a sorcery.

Kefka, Court Mage // Kefka, Ruler of Ruin

Arcane Denial

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep.
You draw a card at the beginning of the next turn's upkeep.