The Mirror Realm
The Tower has a mirrored antiverse that can be entered through reflective surfaces. Entry conditions depend on the surface.
Host: original resident of the tower, lives within the tower
Reflection: counterpart to the host, lives within the mirror realm
The mirror realm is a reflection of the tower. It is a parallel reality of the tower that can be accessed through mirrors and points of reflection. Every person, place, and thing in the tower has its reflection in the mirror realm. The mirror realm is what you see in a reflection. There is no sound in the mirror realm.
Reflection's of mortal residents are mindless and 1:1 mimic their hosts, the person they are reflecting. They are reminiscent of passive, zombie-like reflections.
Reflections of those with mixed divine blood (Godling, Bastard, Half-demon) are bound to the mirror realm, by their mortal side, but can operate independently, by their divine side. They slowly gain consciousness as their host matures.
There are no reflections of those with divine blood (Gods, angels, demons) in the mirror realm. Divine operations occur in the tower and changes are automatically reflected into the mirror realm.
Reflections that leave the mirror realm for the tower come out with varying abilities in light manipulation. Including, but not limited to, light refraction, lasers, hard light, illusions, invisibility, color manipulation, and photon manipulation.