Mighty Fortress

level 8 - conjuration

Casting Time: 1 minute

Range: 1 mile

Components: V, S, M (a diamond worth at least 500 gp, which the spell consumes)

Duration: Instantaneous

Description not available (not OGL).
But here is a summary:

Let erupt a forteresse of stone on a 120 x 120 ft area for 7 days.

Wizard

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