Create or Destroy Channel

Target: a doorway, arch, or other method of passage less than 10 feet by 10 feet in size

You channel the supreme power of admin privileges to create new space bound by a certain set of rules. 

You create a demiplane 20 feet wide and 100 feet long that takes the form of a long, dark, featureless hall, with each end leading to one side of the doorway. Anything passing through the doorway enters the demiplane, and can only move on by exiting the other end, at which point it reappears on that side of the original gate.

As you cast this spell, choose three rules. Creatures within the demiplane must follow those rules if able unless it would cause them direct harm. Creatures that intentionally spend more than 30 in this demiplane become affected by its sheer dullness; after every 30 minutes, each of those creatures rolls a d20. On a result of a 10 or less, they are shunted out of the demiplane and unable to reenter it as they are banned for spamming.

The demiplane's duration is reset each time a creature attempts to dispell it.

Alternatively, you can choose to remove a passageway from existence. The doorway you target becomes surrounded by an invisible force field which prevents living beings or constructs from passing through unless they succeed on a Wisdom saving throw. If they fail, they are pushed 10 feet away and knocked prone.