Sign of Koth

7th-level abjuration (mythos)

Casting Time: 1 turn
Range: Self (60-foot radius)
Components: V, S, M (a platinum dagger and a powdered black pearl worth 500 gp, which the spell consumes)
Duration: Until dispelled You invoke the twilight citadels of Koth to create a field of magical energy in the shape of a 60-foot-radius, 60-foot?tall cylinder centered on you. The only visible evidence of this field is a black rune that appears on every doorway, window, or other portal inside the area.

Choose one of the following creature types: aberration, beast, celestial, dragon, elemental, fey, fiend, giant, humanoid, monstrosity, ooze, plant, or undead. The sign affects creatures of the chosen type (including you, if applicable) in the following ways:

• The creatures can’t willingly enter the cylinder’s area by nonmagical means; the cylinder acts as an invisible, impenetrable wall of force. If an affected creature tries to enter the cylinder’s area by using teleportation, a dimensional shortcut, or other magical means, it must make a successful Charisma saving throw or the attempt fails.
• They cannot hear any sounds that originate inside the cylinder.
• They have disadvantage on attack rolls against targets inside the cylinder.
• They can’t charm, frighten, or possess creatures inside the cylinder.