You need 4 or more enchantments in play for this combo to work.
Cast Day of the Dragons
Starfield of Nyx's ability will trigger, turning all your enchantments into creatures.
Day of the Dragons' ability will exile all creatures and place this amount of Dragon tokens.
Since Day of the Dragons is a creature, it will exile itself, and its second ability will trigger, exiling the tokens and returning all creatures to the battlefield.
This will trigger Day of the Dragons' ability again, exiling all creatures.
The loop will repeat indefinitely, forcing a draw.