Rune Knights enhance their martial prowess using the supernatural power of runes, an ancient practice that originated with giants. Rune cutters can be found among any family of giants, and you likely learned your methods first or second hand from such a mystical artisan. Whether you found the giant's work carved into a hill or cave, learned of the runes from a sage, or met the giant in person, you studied the giant's craft and learned how to apply magic runes to empower your equipment.

This subclass is intended to bring the Rune Knight subclass from Tasha's Cauldron of Everything forward using new terms, rules, and updates from 2024 5th Edition. As many Fighter subclasses saw quality of life improvements and small feature buffs, this subclass will aim to perform the same treatment on the Rune Knight subclass.

Level 3: Bonus Proficiencies

You gain proficiency with smith's tools and can read, speak, and write Giant.

Level 3: Giant's Might

You can imbue yourself with the might of giants. As a Bonus Action, you can magically gain the following benefits for 1 minute:

• If your Size is smaller than Large, you become Large, along with anything you are wearing or carrying. If you lack the room to become Large, your Size does not change.
• You have Advantage on Strength ability checks and Strength saving throws.
• Once on each of your turns, when you hit with a weapon attack or an Unarmed Strike, you can deal an extra 1d6 damage to the target. The damage type is the same as the attack's damage type.

You can use this feature a number of times equal to your Proficiency Bonus, and you regain all expended uses when you finish a Long Rest.

Level 3: Rune Carver

You can use magic runes to enhance your equipment. You know a number of runes equal to your Proficiency Bonus from among the rune options described below, and each time you gain a level in this class, you can replace one rune you know with a different one from this feature.

Whenever you finish a Long Rest, you can touch a number of objects up to your Proficiency Bonus and inscribe a different rune onto each object. To be eligible, an object must be a weapon, a suit of armor, a shield, a piece of jewelry, or something else you can wear or hold in a hand. Your rune remains on the object until you finish a Long Rest, and an object can bear only one of your runes at a time.

If a rune has a level requirement, you must be at least that level in this class to learn the rune. If a rune requires a saving throw, your Rune Magic save DC equals 8 + your Constitution modifier + your Proficiency Bonus. If a rune describes the "bearer" of the rune, the bearer is any creature who is currently wearing or carrying an object inscribed with the rune. Additionally, some runes may be able to be invoked. Once a rune has been invoked, its magic is spent and cannot be invoked again, although the rune still grants any benefits it would otherwise grant without being invoked. Whenever you finish a Short or Long Rest, you can infuse the runes with magic once again, allowing them to be invoked once more.

Cloud Rune

This rune emulates the deceptive magic used by cloud giants. The bearer of this rune has advantage on Dexterity (Sleight of Hand) and Charisma (Deception) ability checks.

In addition, when the bearer of this rune is hit by an attack roll, or when another creature the bearer can see within 30 feet of it is hit by an attack roll, the bearer of this rune can use its Reaction to invoke the rune and choose a different creature within 30 feet of it, other than the attacker. The chosen creature becomes the target of the attack, using the same roll. The magic can transfer the attack's effects regardless of the attack's range.

Fire Rune (7th Level or Higher)

This rune's magic channels the masterful craftsmanship of fire giants. The bearer of this rune has Expertise with all tools they are proficient in and can add their Proficiency Bonus to ability checks made using tools that don't already include their Proficiency Bonus.

In addition, when the bearer of this rune hits a creature with an attack, they can invoke the rune to summon fiery shackles. The target takes an extra 3d8 Fire damage and is Restrained for 1 minute. While Restrained in this way, the target must make a Strength saving throw at the end of each of its turns. On a failed save, the target takes 3d8 Fire damage. On a successful save, the target takes half the Fire damage it would've taken, and the shackles are banished and the effect ends.

Frost Rune (7th Level or Higher)

This rune's magic evokes the unforgiving nature of frost giants and the wintry wilderness. The bearer of this rune has Advantage on Wisdom (Animal Handling) and Charisma (Intimidation) ability checks.

In addition, the bearer can invoke this rune as a Bonus Action to fortify their sturdiness. For 1 hour, the bearer can add their Proficiency Bonus to all ability checks and saving throws that use Strength and Constitution, regardless of whether the ability check or saving throw already includes their Proficiency Bonus or not. For the same duration, the bearer gains an amount of Temporary Hit Points equal to your Fighter level plus your Constitution modifier.

Hill Rune

This rune bestows a resilience reminiscent of hill giants. The bearer of this rune has Advantage on saving throws against being Poisoned, and it has Resistance against Poison damage.

In addition, the bearer of this rune can invoke this rune as a Bonus Action, gaining Resistance to Bludgeoning, Piercing, and Slashing damage for 1 minute or until the bearer is Incapacitated.

Oni Rune

This rune shimmers with the shapeshifting magic of oni. The bearer of this rune's hands grow claws, and their eyes become sharper. The bearer's Unarmed Strikes deal 1d4 + their Strength modifier slashing damage, and the bearer has Darkvision out to 60 feet. If the bearer already has Darkvision, its range is increased by 60 feet.

In addition, the bearer of this rune can invoke this rune as an Action, casting the Alter Self spell using the bearer's Constitution as its spellcasting ability.

Stone Rune

This rune's magic channels the judiciousness and fortitude associated with stone giants. The bearer of this rune has Advantage on Wisdom (Insight) ability checks and Advantage on saving throws made to avoid being pushed or to avoid being knocked Prone.

In addition, the bearer of this rune can invoke this rune as an Action, forcing a creature within 30 feet of it to make a Wisdom saving throw. On a failed save, the creature is Charmed by the bearer for 1 minute or until it takes any damage. While Charmed in this way, the creature is considered Unconscious (without requiring the Prone condition) as it descends into a dreamy stupor. On a successful save, the creature is considered Poisoned until the end of its next turn as they suffer from a wave of drowsiness.

Storm Rune (15th Level or Higher)

This rune's attunement with magic is alike to the storm giants' magical attunement. The bearer of this rune has Advantage on Intelligence (Arcana) ability checks and is under the effects of the Detect Magic spell, as if they had cast it themselves.

In addition, the bearer of this rune can invoke the rune as a Bonus Action, entering a state of heightened magical attunement. For 1 minute or until the bearer is Incapacitated, the bearer has Advantage on all saving throws made to resist spell effects and has Resistance to all spell damage.

Titan Rune (15th Level or Higher)

This rune vibrates with the ferocity of the largest creatures of the land. The bearer of this rune comes under the effect of the Enlarge version of the Enlarge/Reduce spell and their reach with all Melee weapons increases by 5 feet.

In addition, the bearer of this rune can invoke the rune as an Action, causing the ground to shake with every footstep the bearer takes. For 1 minute or until the bearer is Incapacitated, the bearer's Speed is increased by 20 feet, and the bearer does not provoke Opportunity Attacks. Furthermore, when the bearer moves within 10 feet of another creature while under this effect, that creature must make a Strength saving throw. On a failed save, the creature takes 2d10 Bludgeoning damage and is knocked Prone. On a successful save, the creature takes half as much damage and isn't knocked Prone. A creature can only be subjected to this effect once per turn.

Level 7: Larger Might

The extra damage dealt by your Giant's Might feature increases to 1d8.

Level 7: Runic Shield

Your runic magic can now project protective magical shields. As a Bonus Action, you can magically summon the protective shields latent within each of your inscribed runes. Each bearer of your runes within 30 feet of you gains a +2 bonus to their AC until the start of your next turn. Bearers of your runes retain this benefit even should you move further than 30 feet away from them after using this feature. A creature can only benefit from this effect once per activation of this feature.

Level 10: Even Larger Might

The extra damage inflicted by your Giant's Might feature increases to 1d10. Additionally, the magic of your runes permanently alters you. When you gain this feature, roll 3d4. You grow a number of inches in height equal to the roll.

Level 10: Master of Runes

Each of the runes you know from your Rune Carver feature can be invoked twice, rather than once. Whenever you complete a Short or Long Rest, you can reinvigorate your runes with their magic, regaining all expended uses of each rune's invocation.

Level 15: Largest Might

The extra damage from your Giant's Might feature increases to 1d12. Furthermore, when you use that feature, your Size can increase to Huge, and while you are that size, your reach with Melee weapons increases by 5 feet.

Level 18: Runic Juggernaut

Your runic magic waxes to the apex of its strength. The AC bonus from your Runic Shield feature increases to +4 rather than +2. Additionally, your Giant's Might feature now grants you the following additional benefits:

• You have Resistance to Bludgeoning, Piercing, and Slashing damage.
• Rather than applying your extra 1d12 damage to one hit, you may instead opt to apply 1d6 extra damage to each attack you hit on your turn. You make this decision when you take the Attack action, but before you roll any attack rolls on your turn.
• When you are reduced to 0 Hit Points, but not killed outright, you can instead drop to 1 Hit Point and regain Hit Points equal to three times your Fighter level. You can only use this benefit once per use of your Giant's Might feature.

Furthermore, each of your runes can now be invoked three times, instead of twice. When you complete a Short or Long Rest, you may reinvigorate the magic within your runes, regaining all expended uses of each rune's invocation.