This blade acts as a conduit for Thunderous energy. When the wielder attacks with Booming Blade, the hollow nature of this blade amplifies the initial damage bonus of the melee attack.

This blades damage increases when you reach certain levels. At 5th level, the melee attack deals an extra 1d8 thunder damage to the target on a hit. This roll increase by 1d8 at 11th level (2d8) and again at 17th level (3d8)

You gain a +2 bonus to attack and damage rolls made with this weapon, and has the finesse quality due to the hollow blade's dramatically reduced weight.

This blade acts as a regular +2 weapon when Booming Blade is not cast with it.

 

Proficiency with a Longsword allows you to add your proficiency bonus to the attack roll for any attack you make with it.

Notes: Bonus: Magic, Damage: Thunder, Weapon Property: Finesse, Damage, Combat, Versatile, Sap