A wall of thunderous energy forms, centered on the point of your choosing. The wall is up to 25 feet wide, 15 feet tall, and 5 feet thick.
Any hostile creature trying to pass through the wall must first succeed on a Strength saving throw. against your spellcasting DC. On a success, it may pass through (though the wall counts as difficult terrain, meaning the creature must expend 10 feet of movement to pass through the space). On a failure, the creature is thrown back 5 feet from the wall.
The wall also inflicts 3d8 thunder damage (half on a successful save).
Additionally, when the caster loses concentration on the spell (whether willingly or otherwise), they can choose to move the wall up to 30 feet directly forward. Any creature caught in its trajectory must make a Strength saving throw. On a success, the wall passes them by without moving them. On a failure, they are pushed back until the wall reaches the end of its thirty feet movement. This also inflicts 3d8 thunder damage (half on a successful save). This effect does not occur if the spell is dispelled or disabled through other means.
When cast at a higher level, the wall can be up to 10 feet wider and taller, and does an additional 1d8 thunder damage.
* - (A tuning fork)