Sol Ring

Arcane Signet

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

Queen Kayla bin-Kroog

{4}, {T}: Discard all the cards in your hand, then draw that many cards. You may choose an artifact or creature card with mana value 1 you discarded this way, then do the same for artifact or creature cards with mana values 2 and 3. Return those cards to the battlefield. Activate only as a sorcery.

Boros Signet

Containment Construct

Whenever you discard a card, you may exile that card from your graveyard. If you do, you may play that card this turn.