What do people think of this?
Mirror Magic (-4)
Description: You have found a way to draw magic from your own reflection. To use this power, you must have a specific mirror that you are magically linked to. (If your mirror is broken/sealed away, you lose access to this power. However, you do not have to have your mirror with you in order to use it, except where explicitly stated).
Sponsor: Your own reflection.
Agenda: Encourages deception (both deceiving others and self-deception), not looking past the surface, and being concerned more about appearances than reality.
Evocation: Mirror magic allows the use of the spirit element.
Thaumaturgy: This magic allows the use of magic for illusions and psychomancy.
Evothaum: Yes.
Extra benefits: Once per scene, you can use your action for the round to focus on your connection to your mirror to clear two stress boxes (if you do so, any attack against you that round is treated as an ambush). In addition, in a thaumaturgy spell, you can incorporate your mirror in order to double the power of your spell (the control roll(s) for this power is considered to be the same as for the power you called up the normal way). However, if the mirror breaks, every spell that you have cast using mirror magic is broken and you automatically suffer a mental attack equal to double your conviction plus the number of spells you've used your mirror in (to double power) for the last year and a day. You are not protected from this attack by thresholds, distance, mental armor, or any of your magic (other people's magic, however, may protect you). You defend against this attack with discipline.
I also have suggestions for different levels of consequences that this power might inflict, if anyone is interested.