A's Upside Down and Inside Out

You place an illusion inside an area you choose that is a cube up to 50 feet on a side within range.  Choose one of the following effects.

Upside Down: Creatures who enter into this area will suddenly perceive themselves to be walking along its ceiling.  Their hair and belongings will look and feel as though they are still affected by normal gravity towards the 'floor' and the creature(s) may feel compelled to spend an action securing themselves and their belongings. Sounds entering this area from outside the illusion will become deadened and difficult to determine from which direction they came from. 

Inside Out: Creatures who enter into this area will only be able to perceive themselves moving towards its center. Sounds entering this area from outside the illusion will become deadened and difficult to determine from which direction they came from. 

The tactile characteristics of the terrain are unchanged, so creatures entering the area aren't likely to see through the illusion. If the difference isn't obvious by touch, a creature carefully examining the illusion can attempt an Intelligence (Investigation) check against your spell save DC to disbelieve it. A creature who discerns the illusion for what it is can see the normal terrain, and sounds entering the area are no longer diminished.

A blind creature or a creature with (truesight) will be unaffected by this spell.

At Higher Levels. When you cast this spell using a spell slot of 7th level or higher, the spell lasts until dispelled, without requiring your concentration.