Chaos Acumen of Zrin-Hala

This finely tooled warhammer is adorned with ornate filigree. It sparks and sizzles pleasantly in the hand of someone who attunes to it. 

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

Voltaic soul.  When you land the final blow against a creature with this weapon, a bolt of lightning reaches out to a nearby target.

Target a creature within 20 feet, chosen at random (including you and other players). The targeted creature makes a DC 13 Constitution saving throw, taking 2d8 lightning damage, or half as much on save.

On a failed save, repeat this process again up to five times (in the event that there is no successful save).

 

Frayed recollection. When attuning to this item, make a DC 18 Wisdom saving throw.

On a failed save, memories of an important relationship in your life become cloudy and unclear.

On a successful save, you forget some of the minor events that have happened over the last three days.

When removing this item from your attunement, lost memories return. They remain cloudy, however, and some of the effects are permanent (or until magically dispelled, such as with the use of greater restoration).

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

Notes: Bonus: Magic, See "Frayed recollection", Damage, Combat, Versatile, Push