Domain of Corrosion

Some gods are interested in destruction through many different means, but clerics of this domain are granted abilities which despoil, erode, and wear away the people and things they want to destroy in a matter of moments, or to also provide an unnoticeable and creeping decay over time. Whereas many elemental forms are direct and brutal, like fire or lightning, corrosion offers not only immediate harm, but also a subtle and nuanced corruption which can take effect in accordance with a long-term plan. Although this is a favored domain of evil deities, some few goodly ones still utilize it.    

Spell Table

Level	Spell
1st	Acid Stream, Create or Destroy Water
3rd	Acid Arrow, Protection from Poison
5th	Protection from Energy, Stinking Cloud
7th	Blight, Vitriolic Sphere
9th	Cloudkill, Contagion

Bonus Proficiencies

When you choose this Domain at 1st level, you gain proficiency with heavy armor and herbalist's tools. Additionally, you learn the Acid Splash cantrip.    

Corrosive Touch

At 1st level when you choose this Domain, you are granted the ability to channel powerful corrosive magic. You gain a Corrosive Touch, which you may use to inflict harm by rolling a melee spell attack. This inflicts 1d6 + your Wisdom modifier acid damage, and the target must make a Constitution saving throw equal to your spell save DC. If it fails, that target is covered in corrosive fluids, and they must use an action or have an adjacent creature use an action to wipe away the corrosive fluids. Whenever a creature or object covered in corrosive fluids takes acid or poison damage, they add 1d4 to that damage. The initial damage of your Corrosive Touch improves to 1d8 at 8th level, 1d10 at 14th level, and 1d12 at 20th level.    

Channel Divinity: Rusting Grasp

By presenting your holy symbol in one hand and invoking your deity’s power, you cause a hazy, brown, and hissing aura to surround your other hand. Unattended nonmagical metal objects you touch with this hand are instantly rusted and corroded severely, and they will be reduced to dust in 1d4 rounds. You may attempt to target nonmagical metal items, weapons or armors being worn or carried by a creature by making a melee spell attack with disadvantage. If you succeed, you cover the item with rusting dusts, which can be removed with an action or having an adjacent creature use an action to wipe them away. If the dust is not wiped away in 1d4 + 1 rounds, the item in question falls apart and becomes useless. Use of the Mending cantrip can do nothing to restore items lost in this way.

You may alternately use this power to damage metal constructs. Against such constructs, you use your holy symbol and invoke divine power into your other hand, make a melee spell attack, and if you hit, you may deal 3d6 acid damage to that construct. If the construct has acid resistance, it does not apply to this damage. If you miss the melee touch attack, you do not expend your use of this feature, and for up to one minute, you may continue to make a melee spell attack to use this feature. If you expend a Cleric Spell Slot when you use this feature, the construct suffers an additional 1d6 of damage for each spell level of the slot expended.    

Foaming Acids

At 6th level, acid, and poison spells you cast now can create a bubbling, toxic foam which may linger on the target. When you cast a spell that deals acid or poison damage, if that spell required a spell attack and you hit or the targets were forced to make a save and they failed, you may choose to use this feature and affect those targets with foaming acids which linger on the targets. Each target must use an action to wipe away the foam or a creature adjacent to them must use an action to wipe away the foam or at the beginning of your next turn, the spell deals half its damage to the targets again. After dealing this damage, the foam dissolves away. You may use this feature a number of times equal to your proficiency bonus before you must finish a long rest to use it again.    

Divine Strike

At 8th level, you gain the ability to infuse your weapon strikes with divine energy. Once on each of your turns when you hit a creature with a weapon attack, you can cause the attack to deal an extra 1d8 acid damage to the target. When you reach 14th level, the extra damage increases to 2d8.    

Master of Vitriols

At 17th level, you have become enlightened to the greatest secrets and mysteries of corrosion and decay, and you are capable of using the most devastating magical means to achieve this destruction. You add the Disintegrate and Time Ravage spells to the Cleric Spell List. Also, you learn how to cast forth a Dissolving Wave, which is a caustic blast of acidic fluids that rip across the landscape, corroding and singeing everything in its path, leaving noxious fumes in its wake. As an action, you call forth a 30-foot cone of acid and poison, and every creature in that area must make a Dexterity saving throw or suffer 10d6 acid and poison damage. Creatures who fail their save are also overcome with fumes, which inflict a level of exhaustion on creatures who must breathe, and they make all visual Wisdom (Perception) checks at disadvantage until that creature uses an action to wipe their eyes. You may cast a Dissolving Wave twice before you must finish a long rest to use it again. Additionally, you have resistance to acid and poison damage.