Cumulonimbus, the Never-Ending Storm

"After having stolen the very essence of a pure and never-ending storm from the Plane of Air, the Storm King of ages past had placed it upon his mighty anvil and beat into it a shape that pleased him. For one hundred days and nights, he tamed and shaped the essence -- turning it into his weapon of choice for the wars to come with the Dragons. Every strike upon the anvil sent shockwaves and bolts of lightning in all directions, leveling mountains and burning forests. Once finished, it became the very pillar that would hold his influence aloft."

You have a +3 bonus to attack and damage rolls made with this magic weapon.

Properties of the Never-Ending Storm.

Storm King's Anvil. Each attack with this weapon deals an additional 1d6 Thunder damage, an additional 1d6 Lightning damage, and creatures struck by this weapon must make a Constitution Saving throw with a DC equal to your Strength Score or gain the Thunderstruck condition until the end of their next turn.

• Thunderstruck Condition: At the start of your turn, and before moving or taking any actions, you must roll a 1d100 and act upon the result:
  • On an Even result, you take an amount of Thunder damage equal to the result subtracted from 100, then multiplied by 2.
  • On an Odd result, you take an amount of Thunder damage equal to the result.
  • On a result of 49 or fewer, you are Deafened.
  • On a result of 9 or fewer, you are Blinded and Deafened.

Blessed by the Ordning. This weapon requires 2 Attunement slots, but grows in power according to your Size Category. For every size above Large, this weapon deals an additional die of Bludgeoning, Thunder, and Lightning damage and its Reach increases by 5. However, if you are below Huge size, you can only make 1 attack per turn, regardless of any effects that would bypass this restriction. Also, you know how to speak, read, and write Giant while attuned to this item.

Blessed by the Plane of Air. This weapon can be turned into a bolt of lightning and thrown as part of a ranged attack, gaining the Thrown property and a Range equal to 5 times your reach with this weapon. Its Bludgeoning damage is converted into Lightning damage, and If you can see the target, the bolt of lightning will curve and bend around obstacles, ignoring Cover.

Forged for War. When you deal damage with this weapon, a creature’s immunity to Bludgeoning, Thunder, or Lightning is instead treated as Resistance.

 Random Properties.

• 2 minor beneficial properties
• 1 major beneficial property
• 2 minor detrimental properties

Mastery of Advanced Weapons requires military training and skill. To use any of the special properties or the Weapon Mastery properties of the Wrath Maul, you must take the Advanced Weapon Proficiency feat.

Notes: Damage: Thunder, Damage: Lightning, creature with at least 20 Strength or Constitution, Heavy, Two-Handed, Hafted, Momentum, Brutal