Crystal Prison

You attempt to imprison another creature within a rapidly growing crystal. Choose a creature you can see within range to make a Strength saving throw. On a failed save, a creature is considered restrained and [condition]incapacitated[/spell] as a crystal rapidly encases their body. A restrained creature can repeat the saving throw at the end of each of its turns. On a success, the effect ends, and the target takes 2d8 slashing damage as it breaks free of the crystal. If you maintain concentration on the spell for the entire duration, the effect becomes permanent, and the encased creature is put into a state of suspended animation until the crystal is dispelled or broken by an outside force.

While a creature is encased, it is immune to all types of damage, and it cannot lose or regain hit points.