Choose one or more of the following types of creatures: celestials, elementals, fey, fiends, or undead. The circle affects a creature of the chosen type in the following ways:

When you cast this spell, you can elect to cause its magic to operate in the reverse direction, preventing a creature of the specified type from leaving the cylinder and protecting targets outside it.

At Higher Levels: When you cast this spell using a spell slot of 4th level or higher, the duration increases by 1 hour for each slot level above 3rd.