Turn to dust

cast a spherical area of 20 ft. diameter, the time inside of it increases its pace during 1 hour. In that hour, the time that runs inside the sphere is equal to 1 month for each pound of sand using when casting the spell. Medium or smaller creatures that are partly touching or touch the edge of the sphere suffers 8 d10 force damage and are pushed randomly inside or outside of the sphere. bigger creatures touching the edge of the sphere causes the spell to end.

casting this spell with a lvl 9 spell slot reinforce the edge of the sphere making impossible for any creature to physically leave it or travel to other planes.