Hammer of Thunderbolts

You gain a +1 bonus to attack and damage rolls made with this magic maul. This weapon can only be attuned to when you are wearing a belt of giant strength and gauntlets of ogre power . The attunement ends if you remove or change attunement away from either of those items. 

While you are attuned to this weapon and holding it:

• Your Strength score increases by 4 (and can exceed 20, but not 30). 
• When you make an attack roll with this weapon against a giant and roll a natural 20, the giant makes a DC 17 Constitution saving throw or dies. 

You can expend 1 charge and make a ranged weapon attack with the maul with a normal range of 20 feet and a maximum range of 60 feet. On a hit, the maul unleashes a thunderclap heard from up to 300 feet away. The target and every creature within 30 feet of it make a DC 17 Constitution saving throw or become stunned until the end of your next turn.

The maul has 5 charges and regains 1d4+1 charges each dawn.