Entropy's Vessel (5e Equipment)
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Weapon (maul), Artifact (requires attunement)
Chaos is power. It has always been. However, it is impossible to control. What most do not realize is that control is not needed, that "Controlled Chaos" is no chaos at all, but something else altogether. Control is what the weak use to pretend they can rule the strong, a truth that is kept secret to maintain their "order". Those who attempt to tell others this are branded as mad and cast out into exile, never to be spoken to over fear of madness. However, we are not the mad ones, we are the only ones who know this world's truths. May he who take hold of this weapon learn the truth of the world, and they will either embrace the truth, or die denying it.
-Arvis the Mad Sorcerer
This maul is larger than your average maul, and is much too heavy to wield properly until attuned. Once attuned, Its color changes from a dull grayish-black to a randomly shifting assortment of colors, making the weapon difficult to look by anyone other than it's wielder. Once attuned to this weapon, the only way to get rid of it is extremely powerful magic or the death of its wielder.
While attuned to this weapon, the user gains proficiency in Mauls and may ignore this weapon's heavy property.
Entropy's Boon. Upon attuning to this weapon for the first time, and at the start of each day, roll a d4. Until the next roll for Entropy's Boon is made, your attack and spell attack rolls are increased by that number, but your AC is also reduced by that number. When you make a skill check and the results of the roll haven't been announced, you may add the number the rolled on Entropy's Boon to the skill check. The maul regains use of this secondary effect at dawn.
Entropic Focus. Entropy's Vessel can be used as an arcane focus by while equipped, and the wielder may use their spell casting ability modifier instead of strength when making weapon attacks. When the wielder of this mace casts a spell that has a saving throw, as a bonus action, they can make the targets of the spell have disadvantage on their saving throws against the spell. If at least one target fails a saving throw against a spell infused with power from Entropic Focus, roll on the wild magic table. This effect may be used 2 times, and regains all expended uses at dawn.
Critically Chaotic. This weapon can not score critical hits, instead, if your attack roll with this weapon totals 27 or higher, this weapon always hits regardless of the opponents armor class, and applies an added effect based on the current number for Entropy's Boon. If the number rolled on Entropy's Boon is even, the maul deals bonus force damage equal to that number times 3. If it is odd, this weapon deals bonus necrotic damage equal to that number times 2, then you regain hit points equal to the amount of necrotic damage dealt this way. This ability does not apply to spells cast using this weapon as a focus.
Cursed Chaos. As long as you are attuned to this weapon, if you roll an natural 1 at any time you take an action that requires you to roll any number of dice of size d8 or larger, make a Charisma saving throw with DC of 11. If you fail, roll on the wild magic surge table. If you succeed, roll a d6 and add the result to the DC instead. The DC of this effect resets at dawn when upon making your roll for Entropy's Boon. You cannot become unattuned to this weapon by any means other than death or through the wish spell. Use of the wish spell to be either rid of this curse or the weapon itself will cause the weapon to be forcefully unattuned, and it will teleport to a random location on this plane, and remove the curse from the wielder. Using an effect similar to the remove curse spell will suppress this curse until dawn of the next day with the effect of the curse returning upon making the roll for "Entropy's Boon".