Earthen Dome

A dome of hardened earth encloses a creature or object of Large size or smaller within range. An unwilling creature must make a dexterity saving throw or become entombed within the dome for its duration, destruction, until ended by the caster or dispelled. A willing creature does not need to make the saving throw.

If cast as a ritual, a 10-foot-radius immobile dome of hardened stone springs into form above you and up to 8 other willing creatures of medium size or smaller and remains stationary for its duration. The ritual spell ends if you exit the domes coverage.

The dome is 5 inches thick, has an AC of 20 and 200hp, it is however vulnerable to Thunder damage.