In the sixth book of the Night-Watch-Cycle
Anton loses all his powers.
Also, in the spinoff School Watch a djinn appears, which can draw things into existence. this spinoff plays before the sixth book as answered here:
In the story of the spinoff, the djinn creates a new fuaran. Also, after some other stuff happened, the djinn extracts its essence into a bottle, which is given to the inquisition.
Since this essence could be used to create a new fuaran, I was wondering if the person from the main story could regain all powers.