Thunderwave

A wave of thunderous force sweeps out from you. Each creature in a 15-foot cube originating from you must make a Constitution saving throw. On a failure, a creature takes 2d8 thunder damage and is pushed 10 feet away from you. On a success, it takes half damage and isn't pushed. Unsecured objects are pushed 10 feet as well. The thunderclap is audible out to 300 feet. In the Grey Age's silence, that sound carries like a beacon, useful for signaling, terrible for stealth.