Cone AOE spells in DnD 5e are a type of area of effect (AoE) spell that affects an area (obviously) in a cone-shaped pattern that extends outward from a point designated by the caster: this means that you can use the cone to target creatures or areas of effect, and, depending on the spell you use, you can customize its size and shape.

In this article, we will discuss how cone spells work, how to implement them in a DnD 5e game, how to properly represent them visually, and provide tips on how to manage them properly.

What is a Cone in DnD 5e?

Now to understand cone spells, we need to understand what a Cone is inside Dungeons and Dragons 5e: the DMG states that a cone’s width at a given point along its length equals that point’s distance from the point of origin.

So, following these principles, when a cone spell is cast, the caster chooses a point of origin for the spell and extends outward from that point. Its size is determined by the spell’s range and the specific rules for that spell. The cone’s width is equal to its length at any given point, which means that the cone’s area of effect is specified by its maximum length.

For example, a cone spell with a range of 15ft will extend up to 15ft away from the point of origin, and at any point, its width matches its length. Thus, 5ft away from the point of origin, it is 5ft wide, 10ft away is 10ft wide, and so on until you reach the max cone range.

The “issue” with Cone Spells

However, simply from reading the previous definition, you can understand that one of the issues with cone spells is how to properly represent them on a grid.

The rulebooks do not detail how the various spells and other AoE effects must map onto the squares/hexes of a grid. So, it is essential that cone spells feel balanced and are applied consistently.

As a matter of fact, we must understand that any “grids” or such battle maps are just “representations” only. The grids/hexes and how cones/etc. work on them are only designed as a quick reference, not to be overly specific: it is up to the DM to determine how well a cone/effect/whatever would apply to that situation and any outcome of it. Once it has decided how the incantation applies in that environment, it will be the judge in deciding practically which creature may be included in the Area of effects.

But if you are a Game Master, are there any principles you can follow to make the right decisions in this regard?

Let’s take a look at the drawing board.

The different methods on how to draw a Cone AOE in DnD 5e with a Virtual Tabletop

As mentioned before, when the Master tries to implement this description in their Virtual Tabletop, they can choose between few different methods: some DMs prefer maps with grids or hexes, while others prefer a more free-form approach. Using a grid-based map, you can represent the cone as a triangle extending in the chosen direction. You can then count the number of squares that the triangle covers to determine which creatures are affected by the spell.

Alternatively, as a Game Master, you can decide to describe the cone’s area of effect to the players, using the terrain and environment around them as a reference point. For example, you might say, “The cone extends 30 feet in this direction, and it covers all of the goblins standing in this area.” This can be a more immersive and engaging way to handle cone spells, but it can also be more challenging to manage, especially for new players.

Rappresent Cone Spells with Grids

If you are playing on Roll20, you could draw or import a triangular area with the correct size/angle and rotate it to cover the desired area: no need to constrain yourself to 45-degree increments, then. However, a square needs to be at least 50% covered to be affected, and it might not be trivial to determine this for some angles, depending on your math chops.

Take a look at the following image for a representation:

In those cases, have the GM adjudicate it, ensuring the total number of squares covered is L(L+1)/2, where L = length in feet/5 (L = length, in squares, of the cone).

For example, a 15′ cone: 15′ = 3 squares, the total number of squares is 3(3+1)/2 = 12/2 = 6; 30′ cone: 30′ = 6 squares, the total number of squares = 6(6+1)/2 = 42/2 = 21 squares.

Further examples of shapes you can draw

Represent Cone AOE with Free Form

As mentioned, you can also use Free Form to draw these spells. Here is a report made from the lever suggestion designed by Roll20’s user Wilz on how to draw form cones

In this case the suggestions are the following:

• Utilize the Polygon/Line tool (f, g) from the software’s toolkit.
• While holding down the shift key to enable grid snapping, click on an intersection point of the grid to establish the spell’s point of origin.
• Create a triangle by clicking on the canvas. The triangle’s base should have a length equivalent to , and its apex should be positioned at a distance of from the origin point.
• Conclude the triangle by performing a right-click.
• On the side opposite to the point of origin, draw a brief straight line measuring. Alternatively, you can extend the same polygon while ensuring that the opposite ‘tail’ matches the length of . This negates the necessity for step 6, as Aaron astutely pointed out.
• Group the triangular shape with the short straight line. This action permits you to pivot the cone effect around the origin point. Should the origin point need to be shifted, it’s essential to align the entire grouped diagram horizontally or vertically before relocation and rotation.
• Employ rotation to sweep the cone across the display: creatures within the area of effect are impacted if the spell effect covers more than 50% of the square they occupy.

Representing cone in free form is hard, so feel free use this mention as a guideline

How the DM can Manage Cone AOE in DnD 5e

Managing Cone Spells (and Attacks) in DnD 5e requires careful attention to detail and a solid understanding of their work. If you are a Game Master we collected five tips you can use to manage them effectively:

1. It would be best to use clear and concise language to describe the cone’s area of effect. This will help avoid confusion with the players and ensure everyone is on the same page.
2. If you are using a grid-based map, make sure that you count the squares accurately. This can be challenging for diagonal cones, so you may need to use a ruler or other measuring tool to calculate the squares correctly.
3. Remember that cone spells can affect creatures and objects behind the cover, as long as the cone extends past the cover. For example, if a creature hides behind a low wall, a cone spell could still hit them if it extends over the wall.
4. Read carefully how the spells occupy the space: for example, some cone spells have a fixed width that does not increase with distance, while others have a variable width that does increase with distance.
5. Finally, remember that as the GM, you have the final say on how cone spells are implemented in your game. If you feel that a particular method is not working well, you can modify it or develop a new way that better suits your game and players. As always, if there is an uncertain situation, improvise to create the best outcome for that situation.

In the End…

Cone AOE spells are a powerful element to add to any DnD 5e game, but they can be challenging to manage and implement effectively. By understanding how cone spells work and following the tips outlined in this article, you can ensure that cone spells are a fun and engaging part of your game, rather than a source of confusion and frustration. Whether you are a player or a DM, mastering cone spells is an essential skill that will help you to succeed in your adventures and defeat your enemies.

Credits and further reading:

• Learn More about Dungeons and Dragons 5e
• This forum discussion inspires this article
• Also, the following forum post was used as a source
• Learn more about Proficiency Bonus
• Here is the suggestion by the GM Wilz on how to draw