Taka's strength was only at the second step, and this was even with the help of mana. But the domain helped to elevate her power to the fourth step instantly.
This caused her strength to soar from 5E to 2C. Her strength increased by nearly ten thousand times in a short amount of time. This was a remarkable increase in power, but it was not free of consequences.
The main price that she has to pay is that her life and power are now tied to the domain. If the domain becomes stronger, so will she. But if the domain is destroyed, she will also lose her life.
This cost is the main reason why Sword Flash chose an indigene of the world of Aries for the empowerment. Now that her life has been bound to the domain, she will have to do her best to ensure that the domain doesn't fall.
