Commander's Sphere

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

Sol Ring

Arcane Signet

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

Ancient Stone Idol

Flash
This spell costs {1} less to cast for each attacking creature.
Trample
When this creature dies, create a 6/12 colorless Construct artifact creature token with trample.

Cait Sith, Fortune Teller

Lucky Slots — At the beginning of combat on your turn, scry 1, then exile the top card of your library. You may play that card this turn. When you exile a card this way, target creature you control gets +X/+0 until end of turn, where X is that card's mana value.

Blasphemous Act

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