Attunement. An attuned creature can use the Storing Wrath and Unleashing Wrath features of the Wrath of Ion. If it remains unattuned to the creature carrying it for 24-hours, it disappears, reappearing in the hands of someone who will give in to its calling.

Storing Wrath. Upon taking damage while wielding the Wrath of Ion, you may spend your reaction to increase your wrath, gaining one charge up to a maximum of 4.

Unleashing Wrath. As a bonus action, you may spend any number of charges. When you do, you can make a number of melee attacks with the Wrath of Ion equal to the number of charges spent. You then roll a number of your hit dice equal to the number of charges spent. Wrath of Ion causes you to lose hit points equal to the total. This loss of hit points can't be prevented.

Curse. This weapon is cursed,  a fact that is revealed only when you attune to it. Attuning to the Wrath of Ion curses you until you are targeted by the Remove Curse spell or similar magic. While cursed, you're rage builds up over time, potentially causing you to lose control of yourself. For each day that you do not kill a non-construct, non-undead creature, your Hit Point Maximum is reduced by one until you kill or until your attunement is broken. If you do not use the Wrath of Ion to kill at least one non-undead, non-construct creature at least once every 30 days, the Wrath of Ion disappears, breaking the attunement with its user and reappearing in the hands of someone who will give in to its calling.

(Note that "killing" a creature requires you to deal the final blow only when killing is done outside of the initiative order, while in combat, "killing" includes dealing damage to an applicable creature that dies during that combat.)

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

Notes: Damage, Combat, Sap