Beastcaller Savant

Haste
{T}: Add one mana of any color. Spend this mana only to cast a creature spell.

Sol Ring

Chulane, Teller of Tales

Vigilance
Whenever you cast a creature spell, draw a card, then you may put a land card from your hand onto the battlefield.
{3}, {T}: Return target creature you control to its owner's hand.

Arcane Signet

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

Joiner Adept

Lands you control have "{T}: Add one mana of any color."