Our Tempest Cleric had the Wrath of the Storm class ability (strictly speaking, not a spell), and endlessly enjoyed using it. Even when she took a bigger smack than her attacker did in turn, she just enjoyed the free combat.
Also at 1st level, you can thunderously rebuke attackers. When a creature within 5 feet of you that you can see hits you with an Attack, you can use your Reaction to cause the creature to make a DEXterity Saving Throw. The creature takes 2d8 lightning or thunder damage (your choice) on a failed Saving Throw, and half as much damage on a successful one.
So in one game, a Smoke Mephit did its ash breath on the cleric from from the adjoining square. This isn’t a To-Hit roll Attack, but an AoE Affect. Should it trigger Wrath of the Storm?
The answer seems to be NO. Because the AoE weapon isn’t, strictly speaking, hitting with an Attack. The key here is “hits you with an Attack.” And the PHB (p. 194) is clear what that all means:
When you make an attack, your attack roll determines whether the attack hits or misses. To make an attack roll, roll a d20 and add the appropriate modifiers. If the total of the roll plus modifiers equals or exceeds the target’s Armor Class (AC), the attack hits. The AC of a character is determined at character creation, whereas the AC of a monster is in its stat block.
Attacks are made with a d20 roll against a target’s AC. But that’s not what happens with the Smoke Mephit’s breath, or a Dragon’s breath weapon, etc. Those:
are not targeted at someone
don’t require an attack roll
aren’t defended by AC
Instead, AoE attacks create a condition in a certain area of squares, and if someone is in that area, they automatically have to make a Saving Throw to determine the severity of the conditions that ensue (which may or may not include damage; the smoke mephit’s ashy breath caused blindness).
(This is part and parcel of why an AoE attack from an adjoining square doesn’t trigger any Disadvantage, either — because there’s no attack roll to Disadvantage.)
If there’s no attack roll (and, of course, a hit caused by a successful attack roll), Wrath of the Stormdoes not trigger. That would include attacks with Magic Missile, Hold Person, or even Wrath of the Storm itself:
A consequence of this is that if two tempest clerics are fighting one another, and Ann smacks Bob with her mace, Bob may use Wrath of the Storm on Ann as a Reaction, but Ann cannot retaliate in turn, even though she might have a Reaction available, because Wrath of the Storm does not qualify as an attack.
So Thunderwave (PHB 282-83) is a pretty cool spell, and usually ends up in a lot of parties’ repertoire (also in the repertoire of a lot of enemy parties). It does decent damage, an AoE, a push, and the CONstitution save it carries makes it most useful against spellcasters. It does make a godawful racket (carrying 300 feet away, which any DM should take advantage of), but it also scales damage by spell slot.
Overall, a nifty spell. But we’re not going to talk about any of that.
Thunderwave and its Area of Effect
This came up in a game, so afterwards I did some looking into the odd Area of Effect world that is Cubes and Thunderwave.
(There’s a lot about 5e that I respect, but their AoE stuff is kind of janky in general and then the fit onto a grid map — which 5e really sort of dislikes on principle but cannot ignore because a lot of tables really love it, like ours — is even more janky.)
Thunderwave has Range: Self (15-foot cube).“A wave of thunderous force sweeps out from you. Each creature in a 15-foot cube originating from you …” blah blah effects.
So, what does that mean? How does the cube relate to the caster? You would think a Cube AoE would be easy. Yet some of the writing on it approaches being Talmudic in its intricacies to figure out what RAW means here. This is my current interpretation:
You select a cube’s point of origin, which lies anywhere on a face of the cubic effect. The cube’s size is expressed as the length of each side.
A cube’s point of origin is not included in the cube’s area of effect, unless you decide otherwise.
AoE and Grid Maps
DMG 251 notes the following on “Areas of Effect” in relation to grid maps:
The area of effect of a spell, monster ability, or other feature must be translated onto squares or hexes to determine which potential targets are in the area and which aren’t. Choose an intersection of squares or hexes as the point of origin of an area of effect, then follow its rules as normal.
And Xanathar’s echoes this, speaking of “Area of Effect on a Grid”:
Choose an intersection of squares as the point of origin of an area of effect, then follow the rules for that kind of area as normal (see the “Areas of Effect” section in chapter 10 of the Player’s Handbook).
This is one that drives me bats as DM, because everyone wants their spell to be centered in in the center of a square (in origin, in target, in range calculations), and the rule are very clear that is not the case: for where spells start from, land (if not targeting a creature), and calculating the range, it’s all about intersections.
So, standing in a 5×5 grid square, any of the four corners of the square / intersections of the grid are at a range of “self” and are corners that could be the face of the cube you are going to create (including a cube that you are part of, if you are touching the outside face from the inside). Here then would be the possible arrangements I can see:
Cube AoE arrangements
Any of the above can be rotated in increments of 90 degrees.
I.e., you can be on any of the squares outside of the cube, or on the inner squares of the cube, wherever one of the corners of your square touches (red blips) part of the perimeter (side) of the cube. But not in the very center, because you can’t reach that outer face from there.
I’ve not seen anyone actually include the bottom left “corner” example, but it seems to fit the rules to my eyes.
Insider Casting
There is some debate as whether being on the inside of the cube (bottom right-hand two examples) is allowed. I don’t read anything in the above, though, that says it isn’t. That might mean including yourself in the spell effect (but hold that thought for a moment).
Note that though you can be within the cube, for the Thunderwave spell, “the thunderous force sweeps out from you,” so you yourself are not affected when you cast it, even if you are in the area. (Which is a fancier way of saying that you, as the point of origin, are not affected by spells that have a point of origin; a point is not dimensionless, in this case.)
(But Dave, you might be saying, if the point of origin is the grid intersection you are casting from, then doesn’t the thunderous force emanate from that and, if you are inside the AoE, affect you, too? To which I say (1) remember how I said some of this stuff gets Talmudic? and (2) go away, boy, you bother me.)
When would you use a case, of being inside (not the center!) of the cube? Two use cases I can think of:
To reduce the effective effective range to 10 feet rather than 15 feet (potentially important in an indoor combat).
To include a tiny opponent in your own square (an edge case, but a potentially helpful one).
To sum up
So, unless anyone has any objections, that’s how I consider the area for Thunderwave to work.
A home-made game aid for Roll20 that makes life (for me, at least) a lot easier.
For my Princes of the Apocalypse game (which we ran on Roll20 with a standard 5-foot grid), I built some Roll20 AoE templates for spells, to make it easier to see and use the AoE and to provide a longer lasting way to show a still-active area spell.
So why is this needed?
There are ways to show the area of a spell. At a minimum, you can draw something on the screen — but that gets messy and not always easily movable. It’s also hard to draw some shapes, like cones.
Also, even if you draw something with the circle tool, you have two problems — precisely knowing the center point to anchor it on, and, more importantly, clarity on what squares are affected by the spell or not. Yes, you can interpolate (“I think that’s less than half the square”), but that’s just argument fodder.
Roll20 and various adjuncts to it provide area tools for AoEs (Roll20’s native tools have improved dramatically of late), but they still have a couple of problems. First, again, they are actual geometric figures (e.g., circles), so interpolation is still needed. Second, they are non-persistent — you can set them to Linger, but a player can only have one up at a time (I’m not sure if two players can have theirs up simultaneously); you can maybe eke by for that initial Fireball,but if you have a Spike Growth that stays up for a long time, you’re back to drawing a circle on the map.
What I wanted was a way that players could express a proper spell area (cones, squares, circles, even rectangles) in full squares, that they could move as needed for placement, and that would let me (as the DM) resolve the effects on those within the area, whatever the shape, and that could be left on the map for non-instant duration spells.
The answer: AoE templates.
Now coming to a marketplace near you
You can buy spell templates in the Roll20 marketplace. In fact, I did.
Unfortunately, the ones I bought turned out to be one or more of:
Obtrusive (covering up too much of the underlying terrain).
Ugly (a judgment call on my part, to be sure)
Wrong (there are different ways of calculating a 15-foot or 20-foot radius circle on a grid, partly based on whether you are centering on a square middle or on a square corner. Who knew?) (And D&D 5e renders cones differently from other editions or systems.
I wanted something that would be:
Largely transparent — clear enough to be visible, but not blocking the map people were on.
Reasonably attractive
Correct, based on my reading of how (especially) cones and circles/spheres work, including anchoring on a grid vertex (corner), not (except in rare, specified occurrences) on the centers of grid squares.
So, after a couple of failed tries, I decided to roll my own.
Rolling my own
I used a drawing program I have to basically build up a sample AoE as a drawing, trimmed to the edges, with transparency on anything outside of the borders. There would be a grid within the AoE, with solid borders along the grid, and the squares inside tinted but mostly transparent, with a slightly thicker border around the edges to make its boundary clear. I sized it to fit a 70 pixel cell grid.
For a given shape (a 20-foot radius circle, for example), I usually started with something gray. I could then use the color select / color dump functions to remake it into different colors based on the type of spell — orange for a Fireball, green for a Spike Growth, etc.
Once I had a drawing how I wanted it, I uploaded it to my Art Library in Roll20. Then I created an NPC character named, for example, “Fireball (20r)”. I assigned the drawing to it as its image and as its token.
I dragged out a token, sized it to the grid properly, made it into a drawing, and then reassigned that as the token. Lastly, I assigned that character to be seen and controlled by the mage who could throw fireballs.
20-foot radius orange circle
Now when that mage wants to throw a fireball, they can see in an “AoE” folder in their Journal “Fireball (20r)”. They can then drag that out onto the map, move it to where they want their fireball to off, and say, “Hey, DM, your orcs are on fire.” I can easily see the orcs in question, push the fireball token to the “bottom” of the token layer (something which Roll20 does not allow players to do, for some reason) so that I can click on each of those orcs, and start rolling saves …
And, once the excitement is over, I or the mage can easily delete the AoE. Or, if it were a more persistent spell, leave it there for people to see.
Embellishments and Edge Cases
Moonbeam (5 foot radius) AoE token
For some spells, I felt the need to decorate. So, for example, my Moonbeam template has a little Crescent moon in it. And, yes, I did it as a circle, rather than filling up the squares, largely because it’s a small template, and there’s no question which four squares are encompassed by it.
Similarly, for the Dust Devil’s radius of effect, I included a little Dust Devil icon in the center.
Dust Devil (10ft radius) AoE token
The biggest hassle are cones, both because of 5e’s rules, and because the vary in shape depending on the direction they are cast. Which left me, for example, with these two templates for a 15 foot cone.
Diagonal 30-foot coneOrthogonal 30-foot cone
Yes, this is all about the confusion of trying to fit a cone cross-section onto a square grid.
Both of these can be rotated, by the player or DM, in increments of 90 degrees and still line up
The orthogonal one includes a bunch of question marks because of 5e’s cone rules. The basic rule there is that the cone is as wide at a given point as it is long. That means at ten feet away, it’s ten feet wide, etc. But you have to then ask “is that ten feet leaning to the left or to the right?” because, for symmetry, at ten feet away orthogonally, it’s actually a potential range across fifteen feet. So for the diagonals, the player has to say “This cone includes the questionable squares on the left, not on the right” or vice-versa. The alternative is to have two orthogonal templates, and that would be kinda crazy.
The diagonal one doesn’t suffer from that, though it does dredge up the concerns about how diagonals are counted distance-wise on a grid in D&D. In 5e, the basic rule is that a diagonal is as long as an orthogonal — vertical or horizontal — distance, which is nonsense, but quite easy to work with, and the rule we use at my table. Other folk use the older 3.x rule (given as an option in the DMG) that the first diagonal is five feet, the second is ten feet, then five, then ten; under that rule, my diagonal template would need to be changed.
Lastly, cones don’t need to be shot as a straight orthogonal or diagonal — they can be further canted. Fine, whatevs. Since I don’t want to force the players to pick from dozens of templates, they can just rotate one of these partially and we’ll interpolate. The “it’s as wide as it is long” rule makes that a bit easier.
In conclusion
Anyway, this works for my virtual table, and it’s pretty easily extensible as people level up and get new AoE spells of different shades and shapes.
I’ve made a bunch of the ones I crafted early days available here, for you to copy, recolor, and have fun with. Some of them are a bit rough, but that’s what you get for free, and, honestly, the roughness is very rarely visible one the Roll20 desktop.
Part of an ongoing series of 5e Rules notes.
