You brandish the weapon used in the spell's casting and make a melee attack with it against one creature within 5 feet of you. On a hit, the target suffers the weapon attack's normal effects and then becomes sheathed in booming energy until the start of your next turn. If the target willingly moves 5 feet or more before then, the target takes 1d8 thunder damage, and the spell ends.
At Higher Levels. At 5th level, the melee attack deals an extra 1d8 thunder damage to the target on a hit, and the damage the target takes for moving increases to 2d8. Both damage rolls increase by 1d8 at 11th level (2d8 and 3d8) and again at 17th level (3d8 and 4d8).
You endow yourself with endurance and martial prowess fueled by magic. Until the spell ends , you can't cast spells, and you gain the following benefits:
• You gain 50 temporary hit points. If any of these remain when the spell ends, they are lost.
• You have advantage on attack rolls that you make with simple and martial weapons.
• When you hit a target with a weapon attack, that target takes an extra 2d12 force damage.
• You have proficiency with all armor, shields, simple weapons, and martial weapons.
• You have proficiency in Strength and Constitution saving throws.
• You can attack twice, instead of once, when you take the Attack action on your turn. You ignore this benefit if you already have a feature, like Extra Attack, that gives you extra attacks.
Immediately after the spell ends, you must succeed on a DC 15 Constitution saving throw or suffer one level of exhaustion.