Aquan Arena

The next time you hit a creature with a melee weapon attack you create a 5 ft sphere of water (or air if under water) around the creature. When any creature except the caster enters or exits the sphere they must make a strength saving throw or take 1d8 bludgeoning damage and be pushed back. Any ranged attacks made into or out of the sphere are made at disadvantage. If a creature is too large to be encased in the sphere, the spell ends.

At Higher Levels. If you cast this spell using a spell slot of 2nd level or higher, the radius of the sphere increases by 5 ft for each slot level above 1st.