Improved “The Arcane Codex” Warlock Subclass

The Arcane Codex

Warlock Subclass

Command Living Scripture to Protect Your Allies and Control the Battlefield

The patron is a sentient grimoire containing the consciousness of an ancient, powerful wizard who sought immortality. It takes the form of a Codex, tome, scroll, or sheaf of parchment inscribed with living script. Its symbols awaken at your command, shaping themselves into wards that turn aside blows meant for you and those who stand beside you.

Level 3: Arcane Codex Spells

The magic of your patron ensures that you always have certain spells ready. When you reach a Warlock level specified in the Arcane Codex Spells table, you thereafter always have the listed spells prepared.

These spells don’t count against the number of spells you can prepare through your Pact Magic feature, but they otherwise count as Warlock spells for you.

Arcane Codex Spells

Level 3: Script of Protection

Pages of glowing arcane scripture emerge from your Codex and orbit you, forming a protective ward.

As a Bonus Action, you can activate Script of Protection, provided you aren’t wearing armor or wielding a Shield. The Script lasts for 1 minute and grants the following benefits.

Floating Pages. When you activate Script of Protection, two magical pages emerge from your Codex and orbit you. You gain a +1 bonus to your Armor Class for each remaining page, to a maximum bonus of +2.

Expended pages can’t be restored during the current activation.

Sacrificial Burn. When an attack roll hits you while Script of Protection is active, you can take a Reaction to expend one floating page, reducing the damage you take from the triggering attack by 2d6 + your Constitution modifier. The damage can’t be reduced below 0.

The expended page disappears immediately, reducing the AC bonus granted by your remaining floating pages by 1.

Arcane Fortitude. While Script of Protection is active, you have Advantage on Constitution saving throws, including those made to maintain Concentration.

Ending the Script. Script of Protection ends early if you have the Incapacitated condition, don armor, wield a Shield, or expend all your floating pages.

Uses. You can activate Script of Protection a number of times equal to your Charisma modifier (minimum of once). You regain all expended uses when you finish a Long Rest.

Level 6: Intercessory Script

Your mastery of the Codex allows you to extend its protective wards to nearby creatures.

You gain the following enhancements to your Script of Protection.

Greater Script. When you activate Script of Protection, you manifest three floating pages instead of two, increasing your maximum page-based AC bonus to +3.

Intercessory Script. When a creature you can see within 30 feet of yourself is hit by an attack roll while your Script of Protection is active, you can use your Sacrificial Burn Reaction to protect that creature.

You expend one floating page, reducing the damage the protected creature takes from the triggering attack by 2d6 + your Constitution modifier. The damage can’t be reduced below 0.

The expended page disappears immediately, reducing your own page-based AC bonus by 1.

Level 6: Chapter of the Whirling Script

You command your Codex to unleash a swirling storm of magical scripture, hindering enemies while allowing your allies to move freely.

As a Magic action, you create a 30-foot Emanation of floating parchment and arcane writing originating from yourself. The Emanation moves with you and lasts for up to 1 minute. Maintaining the Emanation requires Concentration, as if concentrating on a spell.

While within the Emanation, creatures that aren’t your allies are affected in the following ways:

Difficult Terrain. The Emanation is Difficult Terrain for those creatures.

Obscuring Script. The Emanation is Lightly Obscured for those creatures.

Disrupted Attacks. Those creatures have Disadvantage on Opportunity Attacks.

Your allies are unaffected by these effects.

Chapter of the Whirling Script doesn’t expend or otherwise affect the floating pages created by Script of Protection.

Once you use this feature, you can’t use it again until you finish a Short or Long Rest.

Level 10: Retributive Inscription

Your mastery of the Codex allows its protective scripture to retaliate against creatures that threaten you or your allies.

You gain the following enhancements to Script of Protection.

Greater Script. When you activate Script of Protection, you manifest four floating pages instead of three, increasing your maximum page-based AC bonus to +4.

Retaliatory Shards. When you use Sacrificial Burn, the expended page forms a protective inscription around the creature you protected. The inscription remains active until the start of your next turn, even if Script of Protection ends before then.

Whenever a creature hits the protected creature with an attack roll while the inscription is active, including the attack that triggered Sacrificial Burn, razor-sharp magical words strike the attacker.

The attacker must make a Dexterity saving throw against your Warlock spell save DC. On a failed save, it takes Force damage equal to half your Warlock level (rounded down) plus your Charisma modifier. On a successful save, it takes half as much damage.

This effect occurs each time an attacker successfully hits the protected creature while the inscription is active.

Final Burn. At the end of the combat round in which you used Sacrificial Burn, the expended page’s remaining magic erupts into a burst of flaming scripture.

Each creature within 5 feet of the protected creature that made an attack roll against it while the inscription was active takes Fire damage equal to half your Warlock level (rounded down) plus your Charisma modifier.

This damage occurs whether the qualifying attack hit or missed. A creature takes this damage only once per inscription, and no saving throw is required.

Lingering Inscription. The floating page is expended immediately when you use Sacrificial Burn, reducing your page-based AC bonus by 1. The magical inscription remains active until the start of your next turn, even if Script of Protection ends before then.

Level 14: Manifestation of the Living Codex

You have attained extraordinary mastery over your Codex, strengthening its protective scripture and gaining the ability to manifest its power as a formidable spirit.

You gain the following benefits.

Ultimate Script. When you activate Script of Protection, you manifest five floating pages instead of four, increasing your maximum page-based AC bonus to +5.

Empowered Sacrificial Burn. When you use Sacrificial Burn, the damage reduction increases to 3d6 + your Constitution modifier.

Codex Resistance. Whenever you activate Script of Protection, choose one of the following damage types: Cold, Fire, Necrotic, or Poison. You have Resistance to the chosen damage type until Script of Protection ends.

You can choose a different damage type each time you activate Script of Protection.

Summon Codex Spirit. While Script of Protection is active, you can take a Magic action to expend two of your remaining floating pages and summon a Codex Spirit in an unoccupied space you can see within 60 feet of yourself.

The pages are expended immediately, reducing your page-based AC bonus accordingly.

The spirit lasts for 10 minutes or until it drops to 0 Hit Points. It doesn’t require Concentration and remains for its full duration even if Script of Protection ends.

The spirit shares your Initiative count but takes its turn immediately after yours. It obeys your verbal commands, which require no action from you.

Once you summon a Codex Spirit with this feature, you can’t do so again until you finish a Long Rest.

Codex Spirit

Summoned Creature

Armor Class 17 (Natural Armor)

Hit Points 60 plus 5 for each Warlock level you have above 14

Initiative Shares your Initiative count, acting immediately after your turn

Traits

Fury. The spirit has Advantage on attack rolls against creatures that have the Frightened condition.

Despair. An enemy that starts its turn within 10 feet of the spirit has its Speed reduced by 10 feet until the start of its next turn.

Actions

Multiattack. The spirit makes two Rending Attacks.

Rending Attack. The spirit makes an attack roll using your Warlock spell attack modifier. On a hit, the target takes damage equal to 1d10 + 4 + your Charisma modifier.

Dreadful Scream (1/Summoning). The spirit unleashes a terrifying scream. Each creature of your choice within 30 feet of the spirit must make a Wisdom saving throw against your Warlock spell save DC.

On a failed save, a creature has the Frightened condition for 1 minute.

A Frightened creature repeats the saving throw at the end of each of its turns, ending the effect on itself on a success.

Bonus Actions

Fear. While in Dim Light or Darkness, the spirit can take the Hide action as a Bonus Action.

The Arcane Codex is a homebrew Warlock subclass designed for use with the 2024 Dungeons & Dragons rules.

This is so much better than the previous version! I actually really like it and would play one!
But maybe you could format it with some bold text so that it's a bit easier to read?