Magic Systems & Spells

A magic system is a set of promises you make to your players: what magic can do, what it costs, and what it will never do. Keep those promises and magic becomes a toolbox players plan around; break them and every spell becomes a deus ex machina. This guide covers both halves of the job: designing magic as a piece of your world, and building individual spells that hold up at a 5e table.

Hard Magic, Soft Magic, and Where Your Table Sits

Writers often borrow Brandon Sanderson's framing: the more clearly an audience understands a magic system's rules, the more that magic can be used to solve problems without feeling like a cheat. "Hard" magic has explicit rules and costs; "soft" magic stays mysterious and is better at creating wonder or dread than at solving plot problems.

Tabletop games need both, because players are not readers. They act on the rules you give them, so anything they can cast must be hard. Soft magic belongs to the world around them.

	Hard magic	Soft magic
Player experience	Planning, combos, clever exploits	Awe, fear, uncertainty
Best used for	PC spellcasting, magic items, rituals players perform	Gods, ancient curses, fey bargains, the setting's origin myth
5e example	Spell slots, components, concentration	Divine Intervention, a wish gone wrong, a wild magic surge
Failure mode	Feels like accounting	Feels arbitrary if it solves the party's problems for them

A useful rule of thumb: soft magic may create problems for the party, but only hard magic should solve them.

Source, Cost, Limit: The Three Questions Every System Answers

• Source. Where does power come from: study, a patron, a god, bloodline, the land itself? 5e already splits casters this way (wizards learn, warlocks bargain, clerics are granted, sorcerers are born). Your setting can keep that split or collapse it into one source with different traditions.
• Cost. What does a caster spend? Slots and material components are the mechanical cost; the interesting costs are narrative: social stigma, debt to a patron, physical toll, attention from things that watch the ley lines.
• Limit. What can magic not do? Hard limits ("no magic can return a soul that has been gone a year") make your world's mysteries survivable for the plot.

Then follow the consequences. Raise dead is a 5th-level spell that consumes a diamond worth at least 500 gp. In a world where that is true, diamonds are a strategic resource, temples that can cast it are political powers, and assassination works differently for the rich. Questions like these are what turn a magic system into worldbuilding, and they feed directly into the factions that fight over magic and the institutions that regulate it.

Designing a Homebrew Spell: A Balance Checklist

1. Find the closest official spell. Almost every idea has a neighbor in the Player's Handbook. Start at that spell's level and adjust, rather than starting from zero.
2. Check damage against the benchmark. The 2014 Dungeon Master's Guide gives a spell damage table (below). Single-target spells use the left column, area spells the right.
3. Decide on concentration. Ongoing effects (control, buffs, damage over multiple rounds) should almost always require concentration. A caster can concentrate on only one spell at a time, which is 5e's main brake on stacking.
4. Pick attack roll or saving throw. Saves usually deal half damage on a success; attack rolls deal nothing on a miss but can crit. Match the save to the fiction (Dexterity to dodge, Constitution to endure, Wisdom to resist the mind).
5. Write the upcast line. A typical scaling step is one or two damage dice per slot level above the base.
6. Protect class niches. If your spell does a rogue's job or a ranger's job better than they do, it is too strong regardless of its numbers.
7. Playtest for one arc, then revise. Tell players up front that homebrew spells are provisional.

Spell level	One target	Multiple targets
Cantrip	1d10	1d6
1st	2d10	2d6
2nd	3d10	4d6
3rd	5d10	6d6
4th	6d10	7d6
5th	8d10	8d6
6th	10d10	11d6
7th	11d10	12d6
8th	12d10	13d6
9th	15d10	14d6

Note that fireball (8d6 at 3rd level) is deliberately above this curve. Don't use it as your baseline, or every homebrew area spell will come out overtuned. A spell that adds a rider (a condition, forced movement, terrain) should deal noticeably less damage than the table; a spell that only deals damage can sit right on it. If you want a starting draft to edit, the spell generator produces complete 5e-format spells by level and school.

Making Magic Visible in the World

Players learn your magic system from what they see, not from your notes. Decide a few visible signatures early:

• Sensory tells. Does casting smell of ozone, frost the breath, make animals flee? A consistent tell lets players recognize magic before it is explained.
• Law and economy. Is spellcasting licensed in cities? Are potions sold openly or under the counter? A price list says more about your world than a page of lore.
• Religion. If clerics demonstrably heal, faith is not a matter of belief. How do temples use that?
• History. What magical disaster does everyone remember? One catastrophe on your timeline explains a dozen modern taboos.

Write these down as linked notes rather than a single document, so the rule, the faction that enforces it, and the historical event behind it stay connected. The approach in how to connect your world's lore works especially well for magic, which touches every other part of a setting.

Reading Path: Magic, Spells and Casters

• D&D Wizard: The Complete Class Guide: the eight schools of magic and how 5e's most rules-heavy caster actually plays.
• D&D Warlock: The Complete Class Guide: Pact Magic is the best official model for magic bought from a patron.
• D&D Cleric: The Complete Class Guide: divine magic and how domains tie spells to a god's portfolio.
• D&D Druid: The Complete Class Guide: nature magic, Wild Shape and circles as a regional magical tradition.
• Wild Magic Surge Generator: a ready d100 surge table when you want controlled chaos.
• Magic Item Generator: items are hard magic players can hold; use them to show your system's flavor.
• Potion Generator: everyday magic with color, taste and mechanics for your setting's markets.
• Worldbuilding Questions: 100 Prompts: use the magic and religion prompts to pressure-test your system.
• 10 Worldbuilding Mistakes to Avoid: several of them are magic systems without consequences.

For the wider D&D and TTRPG picture, return to the DnD & TTRPG Resources Hub.

Frequently Asked Questions

How do you balance a homebrew spell in 5e?

Compare it to the closest official spell of the same level, check its damage against the DMG spell damage table, require concentration for ongoing effects, and reduce damage for every extra rider such as a condition or forced movement. Then playtest it and be ready to adjust.

What is the difference between hard and soft magic?

Hard magic has clear, consistent rules and costs, so it can be used to solve problems believably. Soft magic stays unexplained and works best for atmosphere and mystery. In a TTRPG, player spellcasting should be hard; gods, curses and ancient powers can be soft.

How many spell levels are there in D&D 5e?

Cantrips (level 0) plus nine spell levels, from 1st to 9th. Cantrips can be cast at will; leveled spells use spell slots of their level or higher.

How do I create a magic system for my world?

Answer three questions: where the power comes from, what it costs the caster, and what it can never do. Then trace the consequences through your setting's economy, law, religion and history, and make sure players can see those consequences in play.