This spell places a sheath of water around the torso of the target creature. Its pressure deals 1d6 points of damage to the target the first round. It deals an additional 1d6 points of damage each round after that (i.e. on the fourth round you deal 4d6). The target cannot cast spells with verbal components while constricted by this sheath. A successful save each round halves the damage and allows a spellcasting target creature to cast spells with verbal components. Creatures that are normally immune to pressure, such as those that dwell on the ocean floor, gain a +4 bonus to their save.