Rules for playing D&D 5E in an Avatar Universe

So, I'm a huge Avatar fan. Reading the books now (about Kiyoshi), watched the show, love the comics, etc. Been thinking about how to do D&D Avatar. Came to a different conclusion than what most would expect (which would be a sub-class or new classes etc).

RULES FOR AVATAR-THEMED D&D GAMES

LEVEL CAP

The max level you may reach is 10th-level.

Note: This is basically because 6th-level+ spells don't really work in Avatar. Most games end around 10th-level anyway.

ELEMENTAL BENDING

You are a human who comes from one of four cultural backgrounds: the Fire Nation, Air Nomads, Water Tribes, or the Earth Kingdom. Your choice impacts the following:

• Supernatural abilities that you have (Barbarian rage, Ranger's Primeval Awareness, Spellcasting) have their fluff dictated by your culture. A Water Tribe Warlock's eldritch blast could be an icicle; an Earth Kingdom Paladin's Smite is an overwhelming amount of Earth striking the target.
• Corresponding with the list of cultures above, you know one of the following cantrips: Control Flames, Gust, Shape Water, Mold Earth.
• You can change the damage type of non-weapon damage to the element corresponding to your culture: Fire, Thunder, Cold, or Force.

Note: This may seem difficult with more esoteric spells, but its possible! If you're from the Earth Kingdom and you learn hypnotic pattern, take inspiration from the Dai Li and their hypnosis!

ADVANCED BENDING FEATS

At 8th level, you can choose one of the following feats so long as you meet the prerequisites.

LIGHTNING GENERATION

Prerequisite: Born to the Fire Nation

You gain the following benefits:

• You can cast lightning bolt a number of times per long rest equal to your proficiency bonus. Charisma is your spellcasting ability modifier for this spell. This spell only requires somatic components.
• You can change the damage type of non-weapon damage you roll to lightning.
• You are resistant to lightning damage.

SPIRIT BENDING

Prerequisite: Born to the Air Nomads

You gain the following benefits:

• You can cast counterspell a number of times per long rest equal to your proficiency bonus. This spell only requires somatic components.
• When you roll a critical hit with a melee weapon attack, your target creature must make a Constitution saving throw with a DC = 8 + your Wisdom modifier + your Proficiency bonus. On a failure, the target creature cannot cast spells or use magical abilities for 1 minute. At the end of each turn, the creature can make another Constitution saving throw, ending this effect immediately on a success.

BLOOD BENDING

Prerequisite: Born to the Water Kingdom

You gain the following benefits:

• You can cast the spell dominate person once per long rest. Wisdom is your spellcasting ability modifier for this spell. This spell only requires somatic components.
• You can cast the spell crown of madness a number of times per long rest equal to your proficiency score bonus. Wisdom is your spellcasting ability modifier for this spell. This spell only requires somatic components.

METAL BENDING

Prerequisite: Born to the Earth Kingdom

You gain the following benefits:

• When in physical contact with a non-magical object made out of metal, you can freely change the object's shape so long as the object does not increase in size.
• Weapon attacks using metal weapons deal an additional amount of damage equal to your Wisdom ability modifier.
• When wearing metal armor, your AC increases by your Wisdom ability modifier.

BENDING GIFTS

When you create your character, choose one of the Bending Gifts below. These represent something special about your character that makes them unique in the world. In order to choose a gift, you must meet its prerequisite.

AVATAR

You are the avatar, and thus have the capability of learning all four elements. You gain the following benefits:

• You can change the damage of non-magical weapon attacks to: Fire, Thunder, Cold, or Force.
• You can learn any culture's Advanced Bending Feat.
• When you fall to 0 hit points, you enter into the Avatar State - a powerful state of being where you channel the cosmic energy of the entire universe. For a number of turns equal to your Proficiency bonus you are not unconscious, do not make death saving throws, and add your Wisdom ability modifier to all damage rolls you make.

BLIND BENDER

Prerequisite: Born to Earth Kingdom

You permanently suffer the blind condition. However, you have blindsense up to 60 feet, increasing to 120 feet at level 5.

BLUE FLAMES

Prerequisite: Born to Fire Nation

You produce rich, blue flames when you firebend. When rolling fire damage, you can reroll any 1s or 2s, but you must keep the rerolled number.

CLOUD MANIPULATION

Prerequisite: Born to Air Nomads

You have learned to manipulate clouds. You can cast the spell fog cloud a number of times per day equal to your proficiency bonus. Additionally, you can stand on clouds, vapor, and air as if it were solid ground.

COMBUSTION BENDING

Prerequisite: Born to the Fire Nation

Through years of training, you have learned to combust objects with a ray of heat produced from your forehead. As an action, you can make a spell attack with Wisdom as your spellcasting modifier. This attack has a range of 60 feet and deals 1d12 + your Wisdom ability modifier fire damage. This damage increases by 1d12 at 5th and 9th levels.

MINERAL IMMORTALITY

Prerequisite: Born to Earth Kingdom

Through years of training, you have learned to bend the minerals in your own body, decreasing your rate of aging. You age x10 slower than a normal human being. Additionally, your hit points increase by an additional +1 when you gain more hitpoints, and you have advantage on saving throws against paralysis, petrification, and stuns.

My favorite character btw

PLANT BENDING

Prerequisite: Born to Water Tribe

You can manipulate the water in plants for the purposes of your waterbending. As a bonus action, you can gather nearby plant life towards you for one of three uses:

• Arm Vines - Your reach for melee attacks and grapples increases from 5 to 30 feet.
• Swamp Giant - You gather plants around you, creating a giant for you to pilot. Your size increases to large, gain proficiency in unarmed strikes, and your unarmed strikes do 2d10 + your Wisdom modifier in damage.

SUBTLE WIND

Prerequisite: Born to Air Nomads

You have a high level of sensitivity with to changes in air currents. Your passive Perception increases by +5 and you do not suffer disadvantage when fighting or tracking invisible or hidden creatures.

WATER HEALING LEGEND

Prerequisites: Born to Water Tribe

Your ability to heal with water far surpasses anyone elses. When you cast a spell or use an affect that would restore someone else's hit points, add double your Wisdom modifier to the total number of hit points rolled.