Echoing Lance

You emit a targeted burst of intense sonic energy at a target within range. The target must make a Constitution saving throw. On failure, they take 3d8 thunder damage and becomes stunned for the duration by the intense sound. On a successful save, the target takes half as much damage and is not stunned.

At the end of each of its turns, the target can make another Constitution saving throw. On a success, the spell ends on the target, on failure, they take an additional 1d8 thunder from the echoes within the mind

Source: Kibble's Generic Elemental Spells