Squall Bringer (Patreon)

Weapon (battleaxe), varies (requires attunement)

Even the rain from the sky is subject to the Heavenly Dragon's moods; crushing and torrential. When this magic weapon absorbs energy from a dragon’s hoard or its wielder achieves great deeds, it increases in rarity and gains new properties in addition to those of its previous rarities. The DC of any of the properties of this weapon is equal to 8 + your Strength modifier + your proficiency bonus.

Uncommon. While holding this weapon, you have advantage on saving throws to resist being moved against your will.

Rare. You gain a +1 bonus to attack and damage rolls made with this magic weapon.

As an action while holding this weapon, you can summon a rain cloud in the shape of a cylinder that is 10 feet tall and with a 60-foot radius, centered on a point you can see within 100 feet of you. This property fails if you can't see a point in the air where the rain cloud could appear (for example, if you are in a room that can't accommodate the cloud). The cloud lasts for 10 minutes, and you must maintain concentration on this property as though maintaining concentration on a spell. For the duration, constant rain pours from the cloud and the area under it is considered difficult terrain for creatures of your choice.

When the cloud disappears, all water generated from it instantly vanishes. You summon a cloud this way twice per long rest.

Very Rare. The bonus to attack and damage rolls is increased to +2.

If you take the Attack action while under the cloud created by the Rare property, you can swing this weapon to douse your foes with rainwater in place of one of your attacks. Each creature in a 20-foot cone originating from you must make a Strength saving throw. If you are holding this weapon with two hands, the size of the cone is increased to 30 feet. On a failed save, a creature takes 3d8 piercing damage and 3d8 cold damage and is knocked prone. On a successful save, a creature takes half as much damage and suffers no additional effect.

Legendary. The bonus to attack and damage rolls is increased to +3.

The radius of the cloud made using the Rare property is increased to 90 feet. As a bonus action you can move the cloud up to 30 feet.

Rain. As mercurial as the heavens themselves, bringing everything from soothing showers to torrential floods threatening to drown the lands below. Those that wield such power understand their duty as the tip of the spear, washing away any that oppose the Heavenly Dragon. Surge forth, and let nothing stand in your path.