Axe of Grounding

You gain a +2 bonus to your attack and damage rolls made with this magic weapon.

When you take Lightning damage you can use a Reaction to absorb the damage through this magic weapon. This magic weapon can store up to 25 Lightning damage. When it is storing Lightning damage, on a successful hit made with this magic weapon, you can use a Bonus Action to release all or part of that Lighting damage, dealing an additional equal damage to the target.

Topple (Mastery): If you hit a creature with this weapon, you can force the creature to make a Constitution saving throw (DC 8 plus the ability modifier used to make the attack roll and your Proficiency Bonus). On a failed save, the creature has the Prone condition.

Versatile: A Versatile weapon can be used with one or two hands. A damage value in parentheses appears with the property. The weapon deals that damage when used with two hands to make a melee attack.

Proficiency: martial, battleaxe Source: Treasures from Oerth p. 6 (Homebrew)