Star Compass

Oracle Text

Star Compass enters the battlefield tapped.

T: Add one mana of any color that a basic land you control could produce.

Card Rulings

11/17/2017 If a basic land you control gains another basic land type or gains another ability that lets it produce mana, consider those effects when determining what colors of mana that land can produce.
11/17/2017 The colors of mana are white, blue, black, red, and green. Colorless is a type but not a color.