This enchantment is one of many that can be used to create a “place of power” in which the abilities of its resident magician are magnified and hostile forces are weakened. Each day of the month-long ritual, the magician must visit (or inhabit) the space to be warded, moving through the entire space, touching and rearranging it, feeling and manipulating the flow of energy, and negotiating with any local spirits. This process culminates in a draining, dramatic ritual on the final day. Through this process, and by charging various ritually-significant objects (the specifics depend on the caster and the location to be warded) with magical energy and arranging them properly, the casting magician stamps their mark on the warded area’s Shadow, and may manipulate the space in various ways. Some examples:
Environmental manipulation: Within the warded area, factors such as light and darkness, heat and cold, how well sounds carry, and other ambient phenomena can be changed to match the magician’s whim – in extreme cases, their moods and subconscious reactions.
Power attunement: The magician’s personalization of the flow of magic through the space makes it easier for them to cast spells, to detect magical affects in the area, and allows them to make it harder for others to work magic without their permission.
Psychic shielding: The area and persons and objects within it cannot be spied upon, summoned, enchanted, or cursed by anything less powerful than a death-curse or a deity. Furthermore, if a high-quality enchanted mirror is placed within the warded area, the face of anyone attempting to spy in will be shown in the mirror’s surface.
Etc.: Make up your own, as appropriate for your setting!
The base difficulty of this ritual, to cover a space equal to one large room, is d8. One check must be made during each phase of the moon for a month before the ritual can fully take effect. (Expanding the space covered increases the difficulty on a one-step-for-one-step basis.) In the final binding ritual, the magician must sacrifice some number of points from their attributes. Each day of the ritual, fatigue and strain are inflicted on the caster equal to the number of attribute points that will be sacrificed.
While in the warded space, its creator acts as if the sacrificed attributes were never lost; furthermore, any Presence sacrificed is doubled. (E.g. a wizard of Presence 13 who sacrificed three points would have Pre 10 most of the time, but effectively act at Pre16 while in their place of power.) In general, the number of attribute points sacrificed also determine the potency of other effects:
For each point sacrificed, one environmental factor can be changed by one step; checks made to detect and identify magical activity or entities with the area receive +1; the difficulty of hostile magic and similar effects is increased by one step; and one point is removed from the cost (in strain or fatigue) from each spell the creator casts. (Note that magic with a recurring maintenance cost will start imposing a cost in strain or fatigue at some point in the duration, after this “buffer” is used up.)