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D&D Homebrew Classes: How to Design, Balance and Run One
Learn how to build a D&D 5e homebrew class: when to choose a class over a subclass, how to structure features, balance it, playtest it and put it on a sheet.
A good homebrew class starts with one clear fantasy and one central mechanic that no official class already owns. From there you build a 20-level progression on the official scaffolding, check it against existing classes at the same level, and playtest it in short games before a long campaign depends on it. This guide walks through each step and shows how to get the class onto a working character sheet.
TL;DR
Make a full class only if the concept can't be handled by a subclass, a feat or multiclassing. Most ideas fit better as a subclass.
Give the class a central mechanic, a party role and a martial-or-caster position, then spread Core, Strength and Flavor features across 20 levels.
Aim for a sidegrade, not an upgrade: pair unusual strengths with real limits, and compare damage, durability, resources and utility with official classes.
Playtest in one-shots, try to break it on purpose, then revise.
Record the class on a sheet that computes its numbers, so playtesters spend time on the design and not on arithmetic.
Table of Contents
Class or subclass: decide first
Start with the fantasy, not the numbers
Build the class step by step
Balance: aim for a sidegrade
Mistakes that make a class confusing or broken
Playtest like you want it to fail
Putting a custom class on a character sheet
Where Aeternum fits
Perspective
FAQ
Sources
Class or subclass: decide first
Before you write a single feature, check whether the idea already exists. The game has 13 official classes, and many concepts can be handled with feats, multiclassing or subclasses. A dragon-sworn knight, for instance, doesn't need its own chassis: the Oath of the Dragon Knight is published as a Paladin subclass, not a standalone class.
Two practical tests help:
Count the original mechanics. A concept usually works better as a subclass when it needs only one or two new mechanics and still fits an existing class's central mechanic. Mike Myler adds that one genuinely central mechanic can sometimes justify a full class.
Look for dilution. If forcing the idea into a parent class would make the character feel watered down, you probably want a class. The Duskblade is offered as an example: an arcane counterpart to the paladin chassis that is distinct enough to stand alone.
If you land on a subclass, you can still get all the creative payoff with far less balance risk. If you land on a class, read on.
Start with the fantasy, not the numbers
Every strong class opens with a clear fantasy, a narrative identity, a role and a primary mechanic. Each core class also does two jobs: a mechanical one such as damage, defense, avoidance or utility, and a social or roleplaying one. Write one sentence for each before touching a table:
Fantasy: who is this person, and what do they do that nobody else at the table does?
Role: damage, tank, support, control, utility, or a blend.
Position: martial, half-caster or full caster.
Central mechanic: the one thing the class is built around.
The central mechanic should complement the defining mechanics of existing classes. Myler's perspective is that it shouldn't copy them or interfere with them. A mechanic that only repackages Rage or Sneak Attack under a new name isn't a class, it's a reskin.
Examples worth studying
Published homebrew shows how much variety the format holds:
The Accursed is a half-caster built on five Afflictions (Lycanthropy, Misfortune, Possession, Armament and Vampirism), a Jinx touch feature and a Suppress/Afflict control mechanic. It is listed on DMsGuild as a 21-page PDF at $4.95.
Valda's Spire of Secrets is a large collection with 10 new base classes, including the Witch and Gunslinger, plus 150+ subclasses, listed at $30.00.
Matthew Mercer's Blood Hunter is a martial striker. In its 2020 version it has d10 hit dice, Dexterity and Intelligence saves, medium armor and Alchemist's Supplies, and the 2022 version lets Hemocraft use Intelligence or Wisdom.
Notice how each has one idea you can state in a sentence. That clarity is what you want from your own draft.
Build the class step by step
A reliable order, adapted from a widely used class-building outline:
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