Goliath Berserker Greataxe (5e Equipment)
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Weapon (greataxe), very rare (requires attunement)
Even though this giant axe is 10 ft. long, its weight and handle make it usable only in a range of 5ft. It's made from one solid piece of grayish metal with no sheen, almost like stone, and the handle has room for three normal hands. You gain a +2 bonus to attack and damage rolls made with this magic greataxe. In addition, while you are attuned to this weapon, your hit point maximum increases by 1 for each level you have attained.
Unwieldy. If you are a Small or Tiny creature, you cannot use this weapon. If you are a Medium creature with a Strength score of 18 or lower, you subtract your proficiency bonus from the attack roll, but instead you add it to the damage roll. If you are Medium with a Strength Score of 19 or higher, or a Large creature, you don't subtract your proficiency bonus to the attack roll, but still add it to the damage roll. And if you are Huge creature of larger you again don't subtract your proficiency bonus to the attack roll, and can instead add double your proficiency bonus to the damage roll.
Curse. This axe is cursed, and becoming attuned to it extends the curse to you. As long as you remain cursed, you are unwilling to part with the axe, keeping it within reach at all times. You also have disadvantage on attack rolls with weapons other than this one, unless no foe is within 60 feet of you that you can see or hear.
Whenever a hostile creature damages you while the axe is in your possession, you must succeed on a DC 15 Wisdom saving throw or go berserk. While berserk, you must use your action each round to attack the creature nearest to you with the axe. If you can make extra attacks as part of the Attack action, you use those extra attacks, moving to attack the next nearest creature after you fell your current target. If you have multiple possible targets, you attack one at random. You are berserk until you start your turn with no creatures within 60 feet of you that you can see or hear.