The Dusk Phase is the end of your turn, where you can decide to draw a Star Card with Manna or Cultivation Cards.
Drawing Star Cards
Your Dusk Phase is the only time during your turn you may draw Star Cards.
You can draw Star Cards by spending Manna or by playing Cultivation Cards that let you draw Star Cards.
You can draw as many Star Cards as you want, but you can only hold a maximum of 6 Effect Cards in your hand.
The End of the Dusk Phase
Your Dusk Phase is over once you:
(1) have no more Manna to spend on drawing Star Cards
(2) you don't have Cultivation Cards that let you draw Star Cards
(3) or you decide you don't want to draw any more Star Cards.
You signify the end of your turn by passing the Manna Dice to the next player.
Can I immediately play Star Cards I draw during my Dusk Phase?
No. The only thing you are allowed to do during your Dusk Phase is draw Star Cards.
Can I draw multiple Star Cards during my Dusk Phase?
Yes. There is no limit to the number of Star Cards you can draw during your Dusk Phase. If you have the means, you can draw as many cards as you want.
Can I gain additional Manna during my Dusk Phase?
No. The only activity you can participate in during your Dusk Phase is drawing Star Cards.