Carceri

It is a model for every other prison in the multiverse, the Tartan Depths of Carceri are where betrayers, exiles, and the overthrown plot their return. Petitioners consigned to Carceri are most frequently dead traitors, backstabbers, and other souls of underhanded ambition. Most lie compulsively and cunningly. There are many portals into Carceri but very few that lead out.

Magical efforts to leave the plane by any spell other than a wish spell simply fail. Portals and gates that open onto the plane become one way only. Secret ways out of the plane exist, but they are hidden and well-guarded by traps and deadly monsters.

Creatures have disadvantage on saving throws against being paralyzed, petrified, or restrained.