Command Tower

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

Izzet Signet

Exotic Orchard

{T}: Add one mana of any color that a land an opponent controls could produce.

Sol Ring

Kasla, the Broken Halo

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Flying, vigilance, haste
Whenever you cast another spell that has convoke, scry 2, then draw a card.