Empyrean's Maul

You conjure the divine maul of an Empyrean in your hand, which lasts until the spell ends. It counts as a martial melee weapon with which you are proficient. It deals 6d6 bludgeoning damage on a hit and has the Heavy and Two-Handed properties. Once per turn when you hit a creature with this maul, you can force it to make a Constitution saving throw, becoming Stunned until the end of your next turn on a failed save. 

If you drop the weapon, it dissipates immediately. Thereafter, while the spell persists, you can use a bonus action to cause the maul to reappear in your hand.