Creating a Spell
A select group of players will want their character to attempt to create an entirely new spell. Whether they are not satisfied with the current spells in existence or see a way to live forever by having their name attached to a spell, they will approach the DM and beg them to add their newly created spell to the campaign. Whatever the reason, there is a great deal to consider when creating a spell.
The DMG provides some information on how to create a spell from scratch. The first section talks about the general guideline to take into consideration when attempting to build a spell.
When creating a new spell, use existing spells as guidelines. Here are some things to consider:
- If a spell is so good that a caster would want to use it all the time, it might be too powerful for its level.
- A long duration or large area can make up for a lesser effect, depending on the spell.
- Avoid spells that have very limited use, such as one that works only against good dragons. Though such a spell could exist in the world, few characters will bother to learn or prepare it unless they know in advance that doing so will be worthwhile.
- Make sure the spell fits with the identity of the class. Wizards and sorcerers don't typically have access to healing spells, for example, and adding a healing spell to the wizard class list would step on the cleric's turf. (DMG, pg. 283)
Not much to go on. There is a follow-up section on the parameters for damage, but we’ll get into that in a little bit.
When you sit down to start building the spell that will make your wizard more famous, the Bigby himself, there are some basic guidelines you’ll need to follow over and beyond the items listed above. There is a lot to consider before you put pen to paper as you realize you may want to re-evaluate your neutron bomb spell that delivers 50d12 damage with an area of effect of 1 mile. I’m not saying that everything needs to be perfect before you begin to write out your spell. You will need to continuously examine your creation during the process to ensure you have crossed the line from a feasible spell to a massively overpowered arcane magic of mass destruction.
Balance (or don’t ruin the game with your stupid spell)
The biggest requirement when building a spell is making sure it is balanced. The core meaning when the DMG says if your spell is so amazing you’ll be using every spell slot possible for spamming the spell; it’s probably not balanced. Maintaining a certain degree of balance is your number one priority when creating your soon-to-be spell for the ages. Creating a spell that lacks balance, especially in the 5e setting, cannot only ruin the fun for the DM and your fellow players, but it could also be game-breaking which leads to the end of the campaign. No one wants that!
All spells must have a casting time, range, area of effect, how long the spell lasts (duration), a target, and an order in which the spell’s effects occur upon casting. You’ll also need to assign the spell to a specific school of magic, which classes will have access to the spell and what the components needed are. We won’t discuss the last three, but you’ll still need them. Without any of these, your spell is not complete, and you’ll need to go fill in the blanks.
So let’s take a look at a random homebrew spell that I found floating around on the internet that needs work. This will allow us to breakdown any issues as we go through the guidelines for building a spell.
Acid Flood
3rd Level Conjuration
Casting Time - 1 action
Range/Area - 80 ft
Components - V, S
Duration - Instantaneous
Attack/Save - None
Damage/Effect - Blinded
Classes - Bard, Sorcerer, Warlock, WizardYou conjure a 20ft by 8ft wave of acid. Those who get hit by the acid take 6d10 acid damage, and half if successful.
At Higher Levels: Per Spell Slot higher than 6th level, add 2d10 to the damage.
Yep, someone actually made that spell…
Getting started
The easiest way to write a spell is to use other spells to compare yours to. It will help in keeping the spell balanced and assist in the wording of the spell. You don’t want to copy a spell and increase the damage or extend the range. The WotC team has already figured out how to balance the spell, so you can be confident that changing it with throw that balance off. It will help is using comparable amounts of damage by level, what school of magic your spell belongs to, and how to properly word your spell so it is clear and covers the purpose of what you want your spell to do. For our spell, we will be comparing it to the tidal wave spell.
Tidal Wave
3rd-level conjuration
Casting Time: 1 action
Range: 120 feet
Components: V, S, M (a drop of water)
Duration: Instantaneous
Attack/Save - Dex save
Damage/Effect - Bludgeoning/Prone
Classes - Druid, Sorcerer, WizardYou conjure up a wave of water that crashes down on an area within range. The area can be up to 30 feet long, up to 10 feet wide, and up to 10 feet tall. Each creature in that area must make a Dexterity saving throw. On a failed save, a creature takes 4d8 bludgeoning damage and is knocked prone. On a successful save, a creature takes half as much damage and isn't knocked prone. The water then spreads out across the ground in all directions, extinguishing unprotected flames in its area and within 30 feet of it, and then it vanishes
Casting Time (or how long to I have to wait to blow you up)
Most spells have a casting time of an action, bonus action, or reaction. Some have longer casting times that can be anywhere from 1 minute to 24 hours, including spells that be cast as a ritual. For the sake of my sanity, we will be talking only about the first three options.
Most spells require an action to cast. A spell with a bonus action prevents the caster from using their action to cast another spell, but they can cast a cantrip. Secondary casters such as the paladin or ranger can make the best use of bonus actions spells. For example, a ranger can use their bonus action to cast a hunter’s mark spell before using their action to fire their arrow at the poor kobold that has now been marked as their quarry. Reaction spells are probably the rarest of all spells. As with all reactions, the spell is cast in response to an event. The reaction spell that most people know is the shield spell. Reaction spells need to be clearly defined so the caster knows precisely when the spell can be cast.
When creating a spell you should factor in the amount of damage or effects the spell does when deciding the casting time. A bonus action spell is a great gift to bestow upon a character, so you’ll want to reduce the amount of damage or healing the spell will provide. Reaction spells are powerful simply because they let you cast outside your normal turn, so they should be nerfed down even further. If you want to increase the damage/healing of a spell, you can increase the length of time it takes to cast the spell.
Our example spell has a casting time of 1 action, which is fine given the spell’s purpose.
Range/Area (or from how far away & how many I can kill)
The range is how far you can cast the spell. A target must be within the range of the spell you are casting. It can be a creature, a point in space, or you. Spells that are cone spells or line spells are listed as a range of self, but this means you are the spell's origin point. The range is usually expressed in feet, although some spells have larger ranges such as a mile.
The area is the space your spell’s effects take place in. There are five primary shapes that an area of effect occurs, including a cone, cube, cylinder, line, and sphere. As stated above, you are the point of origin for cone and line spells, which means when you stretch out your arm, point your finger, or maybe stick out your tongue, magical energy will burst forth from it. Most other spells have a fixed origin somewhere with the spell’s range, and that’s where the magical effect will start.
When you create your spell, your area of effect dictates the damage/healing and or effects the spell should have. A simple rule of thumb is the bigger the area of effect, the lower the damage should be. The difference between a 20 ft. radius and a 40 ft. radius is massive. I’m a visual person, so I drew it out on my grid map. If you’re fighting a small army of kobolds, 20 feet may kill a lot of them, but at 40 feet, you have a high probability of killing all of them.
Looking at our spell, we can see that it has a range of 80 feet. There isn’t anything wrong with 80 feet, but it does not conform to the standard range of most spells. Usually, similar spells are 30/60/90/120 feet, but nothing says a spell needs to be confined to those measurements. Tidal wave has a range of 120 feet, so that should be the starting point we work with for the spell’s range. The wording needs some work, so we’ll adjust that after we fix the area of effect.
The area of effect is quite odd, and the wording needs to be corrected. Our spell states that “You conjure a 20ft by 8ft wave of acid.” Let’s assume that means the spell is 20 feet long and 10 feet wide, so we’ll need to add a height to our spell. We’ll also need to change the wording since the way it is written now, the spell is fixed at these measurements and does not allow the caster to adjust as needed. Finally, let’s change the spell's width to 10 feet since most spells use measurements in 5 feet increments, and we are going to round up.
So our new range and area descriptive text is now as follows:
”You conjure up a wave of acid on an area within range. The area can be up to 20 feet long, up to 10 feet wide, and up to 10 feet tall.”
Duration (or how long is this going to hurt)
How long the spell keeps on giving, whether it’s healing or damage. The duration can be anywhere from one round to a year, with some spells lasting until they are dispelling or wiped from existence. Instantaneous spells are immediate, and while the effects cannot be dispelled, there’s always the crafty wizard that will use the ever-annoying counterspell. But I digress. Concentration is when the spellcaster has to maintain their focus to keep the spell going. Most, but not all, spells that last longer for a round requires concentration. You can move around, attack, and even cast another spell, so long as it does not require concentration also, or you’ll lose concentration on the first spell. Don’t get hit by an attack either, as that will cause you to lose concentration.
When building your spell, you need to balance the damage, healing, and other spell effects with the length of its duration. For example, instantaneous spells can deliver a huge burst of damage in a single round. A spell that causes immediate damage followed by additional damage every round (usually requiring concentration) should have a lower burst in the first round, as it is the spell that keeps on giving. The same rule applies when giving a spell additional effect over and beyond damage.
Our spell has a duration that is instantaneous. It is appropriate for the spell and its purpose.
Target (or who do I get to hurt)
A target can be an individual or a group. When making a spell, you’ll need to specify if your spell targets creatures, objects, or a point of origin for an area of effect (see above). A single creature target will usually include being able to target yourself, but I recommend not doing that with damage spells. A point of origin is the starting point from where the magical energy will be released. Whether it be a square, sphere, or cylinder, you’ll have an opportunity to affect any number of creatures or objects that are standing within it.
For our acid spell, the target is any point of origin within the 120-foot range. We were able to define this when we re-wrote on range/area description, so we are in good shape.
Damage, Saves, and Effects (better known as the good stuff)
This is why you’re writing the spell. We want to know you much the spell helps or hurts and what the target can do about it. Referring back to the DMG, we can find a damage chart which is a great starting point.
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 10d6
7th 11d10 12d6
8th 12d10 13d6
9th 15d10 14d6
I say starting point since nothing is tying you to these exact numbers, and in fact, they should be adjusted up or down, depending on what additional effects you want to give the spell. The chart assumes that a target will take half damage if they make a saving throw. If there is no save involved with your spell, then the damage should be reduced. The same goes for adding some additional effect that occurs. The damage and the save usually are tied to one another, as the order in what the spell does should be clearly spelled out in the text. This is sorely lacking in our spell.
There are several other problems with our spell. Here’s our current wording. “Those who get hit by the acid take 6d10 acid damage, and half if successful.” The damage is a bit too high, you have an effect mentioned in the spell’s stat block that is not referenced at all, and the spell description mention half damage with no save information provided in either the stat block or the text. So let’s get to fixing this spell to make it somewhat useful.
Once we cast our spell, if we want the target(s) to make a save, it needs to be the next item in the description to know what happens before we can figure out damage/effects. Since your target will try their hardest not to stand there and let a wave of acid wash over them, they will want to try and dodge it. A Dexterity save needs to be added to the description. “Each creature in that area must make a Dexterity saving throw.” One simple line conveys to the reader that everyone inside our 20 feet long, up to 10 feet wide, and 10 feet tall wave of acid is required to make a save. We also know what type of saving throw they will be making.
Now we can move on to everyone’s favorite part, the consequences our targets will endure. Since there is no mention of being blinded in the description, but it is apparently something that can happen, we’ll need to add that. Next, we’ll need to correct the damage. 6d10 is already higher than the recommended number of damage dice for a single target, let alone multiple. Second, acid is a decent damage type, as only 18 creatures have resistance to it (although 15 of those creatures are immune). Third, you have the chance of being blinded, so the spell's damage should drop our damage even further. Since 6d6 is the baseline for a 3rd level spell, we will drop it down to 4d6. Now I know you may be saying, “But the tidal wave does 4d8!” True enough, but it’s bludgeoning damage which is much more common, and being knocked prone is a tad less powerful than being blinded. The blinded condition can last for multiple rounds if you fail additional saves while being prone does not. I feel comfortable with our adjusted damage.
Next, let’s make sure people know what happens when you succeed or fail the saving throw. Making the save usually means taking half damage and not being subjected to any additional effects/conditions. We also need to set a maximum length for our blinded condition. We could always let the poor sod be blinded forever, but that feels like a 1st edition spell, and we don’t want to be that mean. Our next few lines will be as follows: “On a failed save, a creature takes 3d6 acid damage and is blinded for 1 minute. On a successful save, a creature takes half as much damage and isn't blinded.”
Since our wave doesn’t get to go anywhere, we’ll need to make sure that we let people know a giant swell of acid isn’t going to be chasing them down the street. In addition, we need to tell the reader how and when they can attempt to end the blinded condition. We’ll end our spell with, “The acid immediately disappears into the ground. A blinded target can make a Constitution saving throw at the end of each of its turns. On a successful save, the effect ends.” Finally, we will eliminate any scaling the spell may not. Quite simply, it’s not needed.
Our new and improved spell now looks like this.
Acid Flood
3rd Level Conjuration
Casting Time - 1 action
Range/Area - 120 ft
Components - V, S
Duration - InstantaneousAttack/Save - Dex save
Damage/Effect - Acid/Blinded
Classes - Bard, Sorcerer, Warlock, WizardYou conjure up a wave of acid that slams down on an area within range. The area can be up to 20 feet long, up to 10 feet wide, and up to 10 feet tall. Each creature in that area must make a Dexterity saving throw. On a failed save, a creature takes 4d6 acid damage and is blinded for 1 minute. On a successful save, a creature takes half as much damage and isn't blinded. The acid immediately disappears into the ground.
A blinded target can make a Constitution saving throw at the end of each of its turns. On a successful save, the effect ends.
Our spell is now ready to send out to the world. I’ll be the first to admit this spell isn’t anything special, just an acid version of the tidal wave spell. That’s ok, though, as starting simple is the best route to take when creating homebrew. We may all dream of writing the next storm of vengeance or wish spell, but in reality, creating the simple acid wave spell is the perfect place to start.
If you like our articles, love homebrew, and are looking for a fun and active community to talk about all things D&D, consider supporting us on Patreon. Below are some of the benefits we offer:
Access to our Homebrew Horde with over 300 items and counting!
Vote on upcoming Deep Deep topics
Monthly online one-shot adventures
Early access to Deep Dive and Rewind Articles
Even more Homebrew in our Magic Item Monday and Monster Thursday series
More to come!
