R: Touch D: Sigil

You transform a building in a powerful vessel for your spells: You engrave your sigil on the floor somewhere in a building and choose another spell you know. You then spend 1 day per room in that building carving a complex set of formulas and runes.

As long as the rooms in building are intact, you can cast the chosen spell from the location of your sigil with the same amount of spell dice as there are rooms in the building. Doing so expends one of your spell dice for the day.

Architecture + Formula

By SaltyGoo