Yamato

Conjuration Casting Time: 1 action Range: 60 feet Components: V, S, M (a vial of water) Duration: Concentration, up to 1 minute You create a sphere of water around a creature within range, trapping it inside. The trapped target suffers 4d8 cold damage plus your intelligence modifier at the beginning of each turn as long as it is inside the sphere of water. The target must make a Strength saving throw or be restrained. A restrained creature can hold its breath for a number of rounds equal to its Constitution modifier (minimum 1). At the end of each of its turns, the target can make a Strength saving throw to break free.