Ethereal Partition

You focus your magical energies into a door or hallway you can see, and create a barrier that fills the hall completely, and can be seen through. The barrier can be no larger than a 30-foot square in area, and must be anchored on the floor and at least one wall. The barrier extends into the Ethereal plane, and for the duration of the spell, no creature can move directly from one side of the barrier to the other.

The barrier itself has a pool of hit points equal to your hit point maximum * 3, on each turn a creature is able to make one attack against the barrier, which has an Armor Class of 15, and is resistant to all attacks made by non-magical weapons. If the barrier reaches 0 hit points, the barrier is destroyed and the spell ends. Additionally, you are unable to move more than 10 feet from the original casting location, or the barrier will be destroyed and the spell will end.

Additionally, spells cast from one side of the barrier cannot pass to the other side, instead stopping at the barrier and causing it's normal effects as if it were blocked by a transparent wall. Spells that require a Strength, Dexterity, or Constitution saving throw by the wall are automatically failed, while spells that require an Intelligence, Wisdom, or Charisma saving throw are automatically succeeded by the barrier, as it has no mind to trick, confuse, or bewilder, but does have a body that can be harmed.

This spell can be cast as a ritual. When cast as a ritual, extend the casting time by 10 minutes, and extend the duration to 1 day.