Fighter - Bone Knight

by somanyrobots

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Fighter Archetype

Bone Knight

Bone Knights are warriors with necromantic training, augmenting their martial skill with bursts of bone magic. Some are former necromancers-in-training, drawn to another discipline by circumstance or inclination. Others never sought a life besides combat, and choose to learn the most brutal magics they can.

To walk the path of a Bone Knight requires arcane training, so many come from scholarly or wealthy backgrounds. Others, though, are drawn to necromancy by the macabre setting of the battlefield, and come from any background. Very few Bone Knights will hold to a purely goodly alignment; the compromises and blasphemies required are typically too extreme for that.

Bone Knight Features

Fighter Level Features
3rd Spellcasting, Bonetouched Blade
7th Bone Shell
10th Instant Osteomancy
15th Dreadful Magics
18th Champion of Bone
Necromancer? What's That?

The Bone Knight is (mostly) a 1/3-necromancer, which is a dedicated necromancy class available here. Most of the associated new spells can be found here.

Spellcasting

When you reach 3rd level, you augment your martial prowess with the ability to cast spells. See Spells Rules for the general rules of spellcasting and the Necromancer Class for the necromancer spell list.

Cantrips

You learn three cantrips from the necromancer spell list. You learn an additional necromancer cantrip at 10th level.

Spell Slots

The Bone Knight Spellcasting table shows how many spell slots you have to cast your necromancer spells of 1st level and higher. To cast one of these spells, you must expend a slot of the spell’s level or higher. You regain all expended spell slots when you finish a long rest.

Spells Known of 1st-Level and Higher

You know three 1st-level spells of your choice from the necromancer spell list.

The Spells Known column of the Bone Knight Spellcasting table shows when you learn more spells of 1st level or higher. Each of these spells must be a necromancer spell of your choice, and must be of a level for which you have spell slots. For instance, when you reach 7th level in this class, you can learn one new spell of 1st or 2nd level.

Whenever you gain a level in this class, you can replace one of the necromancer spells you know with another spell of your choice from the necromancer spell list. The new spell must be of a level for which you have spell slots, and it must be a necromancer spell.

Spellcasting Ability

Intelligence is your spellcasting ability for your necromancer spells, since you learn your spells through innate ability and practice. You use your Intelligence whenever a spell refers to your spellcasting ability. In addition, you use your Intelligence modifier when setting the saving throw DC for a necromancer spell you cast and when making an attack roll with one.


Spell save DC = 8 + your proficiency bonus + your Intelligence modifier


Spell attack modifier = your proficiency bonus + your Intelligence modifier

Spellcasting Focus

You can use an arcane focus or any melee weapon you are wielding as a spellcasting focus for your necromancer spells.

Bonetouched Blade

Additionally at 3rd level, your dark magic empowers your attacks. When you cast an osteomancy spell with a casting time of 1 action, your next weapon attack within 10 minutes deals 1d8 bonus necrotic damage.

This bonus damage increases to 2d8 at level 10 and 3d8 at level 18.

Bone Shell

Also at 7th level, you can conjure an armor of cursed bone for yourself over the course of a 1-minute ritual. This armor acts as a ward with hit points equal to your fighter level, with vulnerability to bludgeoning damage and resistance to all other damage types. When you would take damage, the ward takes it first instead. When the ward is reduced to 0 hit points, you take any remaining damage and it then explodes, forcing every other creature within 10 feet of you to succeed on a Dexterity saving throw or take 1d6 piercing damage and 1d6 necrotic damage.

You can create this ward once, regaining the ability when you finish a short or long rest.

Applying damage to a vulnerable ward requires a little bit of math; apply damage to the ward, doubling it, until the ward breaks, and then apply the remainder to the PC. For example, if the ward has 10 hit points and you get hit for 20 bludgeoning damage, the ward would absorb the first 5 and the remaining 15 would apply to the PC.

Instant Osteomancy

At 10th level, you learn to cast your dark magic especially swiftly. You can cast a necromancer spell with a casting time of 1 action as a bonus action instead. Once you do so, you can't do so again until you finish a short or long rest.

Bone Knight Spellcasting
Level Cantrips
Known
Spells
Known
1st 2nd 3rd 4th
3rd 3 3 2
4th 3 4 3
5th 3 4 3
6th 3 4 3
7th 3 5 4 2
8th 3 6 4 2
9th 3 6 4 2
10th 4 7 4 3
11th 4 8 4 3
12th 4 8 4 3
13th 4 9 4 3 2
14th 4 10 4 3 2
15th 4 10 4 3 2
16th 4 11 4 3 3
17th 4 11 4 3 3
18th 4 11 4 3 3
19th 4 12 4 3 3 1
20th 4 13 4 3 3 1

Dreadful Magics

At 15th level, your spells can crack open your enemies' armor, making them ever-more vulnerable. When you deal bonus damage to a creature with your Bonetouched Blade, the next saving throw that creature makes against one of your spells is made with disadvantage.

Champion of Bone

At 18th level, all your osteomantic powers gain increased range.

  • When you deal bonus damage with your Bonetouched Blade, you can choose to deal half as much bonus damage to a second creature adjacent to your target.
  • Your Bone Shell's explosion radius increases to 20 feet, and you can exempt a number of creatures up to your Intelligence modifier.
  • You can now use your Instant Osteomancy twice, regaining both uses after a short or long rest.

Bone Knight quirks

The following are some optional quirks for a player of this Domain to choose from.

d6 Quirk
1 Your armor is adorned with skull and bone motifs.
2 You exclusively use bludgeoning weapons; you like the crunch.
3 You deride true necromancers as "mere theoreticians".
4 Your pupils are shaped like skulls.
5 Your skin is stretched tight, revealing the skeleton underneath.
6 You have a bubbly and fun-loving disposition.

Change Log

v0.2

  • Adjusted language on Bone Shell
  • Added math example for Bone Shell

v0.1

  • Initial Draft!
Credits & References:

Art

Josu Vess, Lich Knight, by Tyler Jacobson © Wizards of the Coast LLC


Background Image Stains

Jared Ondricek


License

© 2026 somanyrobots, CC BY-NC 4.0


Includes spells from Kibbles' Casting Compendium 2.0 by KibblesTasty Homebrew LLC, which is licensed CC-BY and available here.


Includes spells from Spells That Don't Suck by Omega Ankh and somanyrobots, which is licensed CC-BY and available here.


Fan Content Policy

This work is unofficial Fan Content permitted under the Fan Content Policy. Not approved/endorsed by Wizards. Portions of the materials used are property of Wizards of the Coast. ©Wizards of the Coast LLC.


5E SRD Content
  • This work includes material taken from the System Reference Document 5.1 (“SRD 5.1”) by Wizards of the Coast LLC, available here.

  • The SRD 5.1 is licensed under the Creative Commons Attribution 4.0 International License available here.