How do you use colorless mana?

[milkyway4211]

https://gatherer.wizards.com/Handlers/Image.ashx?multiverseid=380446&type=card

So does this mean that colorless mana doesn't empty from any player's turn?

[Drunk Cynic]

No. Normally, mana pools end at the end of each step or phase. Instead, the replacement effect of Kruphix, God of Horizons, takes any mana left in your mana pool at the end of a step or phase, and makes it colorless. It remains in your mana pool until used. Over time, you will end up with a reserve of colorless mana in your mana pool.