Creatues you control can tap to produce at least ({2} magic symbol) .
Gilraen does not have summoning sickness.
Steps
Declare Aurelia as an attacker.
Aurelia triggers, untapping all creatures you control and causing you to take an extra combat phase after this one.
Activate any number of creatures you control by tapping them, adding at least ({2} magic symbol) .
Activate Gilraen by paying ({2} magic symbol) and tapping it, blinking Aurelia.
Repeat each combat phase.
Notes
You can perform steps 3 and 4 before combat damage is dealt to ensure Aurelia does not die, or you can do so after damage is dealt but before the combat phase ends to deal combat damage.