The Academy

Guarded by charms which hid it from those not specifically seeking it and warned of an intruders approach, the Academy was a demonic outpost in the mortal realm run by Ludlow. The Academy boasted doors capable of becoming immaterial as well as an incredibly powerful force-field capable of repelling physical strikes, energy balls, and even a hasty spell cast by the Charmed Ones.

The force-field completely sealed the Academy, even against entry by orbing. Only repeated strikes by Piper Halliwell’s molecular combustion blasts were able to eventually breach it.