AvocaD&D and Tabletop Gaming

Welcome back to the weekly D&D and Tabletop Gaming thread!  Here’s a place where we can talk about Dungeons & Dragons or any other tabletop games that you nerds might be into.  Tell us about the games you’re playing, speculate about future expansions, recruit your fellow Avocados into new groups, whatever you want.

Many spells in D&D can cover an area of a given size and shape and affect any creature that is within that area. Determining how many creatures are in a given area of effect at any time can often be challenging for both players and DMs, whether you’re playing on a square grid battlemap, a hex map, or just using the “theater of the mind.” If you’re playing with a map, the trouble usually comes from representing a 3-dimensional effect on a 2-dimensional space.

The simplest area of effect is the line. A line extends in a straight path from its point of origin (usually the spellcaster) up to its length and hits every creature that it passes through. For example, the Lightning Bolt spell affects creatures in a line 100 feet long and 5 feet wide, which means it maps very nicely onto a standard grid. Pick a square adjacent to the caster then just follow that line until you hit 20 squares. For the most part this will be pretty straightforward. You might spark some debate at the table if your line is running on a diagonal, but most often the trouble with lines is going to come when a player wants to avoid hitting their friends. For instance, is it possible to cast a Lightning Bolt at an upwards angle so you can target the fire giant without hitting your halfling buddy who’s standing directly in the path? If you’re just counting squares on your 2-D grid, your halfling friend is going to get fried. But it seems obvious that in the imagined 3-D space of the world, you can aim over the head of a 3-foot-tall creature and still hit a 20-foot-tall creature along the path, without even really needing any knowledge of trigonometry.

Spells that create cylinder or sphere effects are also fairly easy to adjudicate. Start from any intersection between two lines on the grid (ie, the corner of a square rather than the center of the square) and just count out the radius. For example, Moonbeam‘s 5-foot radius means it affects 4 squares on a grid, centered where all 4 corners meet. Larger radius effects can lead to some issues–the edge of the circle may pass through a small corner of a square on the grid, and it can be unclear whether a creature in that square is in the spell’s area or not. A good rule of thumb is that at least half of any square needs to be inside the circle for the square to be affected. A cylinder effect almost always includes the ground, and though spells do specify a height, it’s usually irrelevant (unless you’re fighting a flying creature that’s trying to keep out of range). With spheres you can usually choose any point in space, which means you’ll often have players centering their Fireballs in the air behind the creature(s) they want to hit to avoid catching the other PCs in the blast.

Spells that create cone affects, like Burning Hands, can also be a little confusing. A cone extends in a straight line from the point of origin, but the width of the effect is equal to its length at any given point. In effect this means a you start with a square adjacent to the caster’s, then the next row would cover two squares, then three squares, etc, until you reach the maximum length. This can lead to some irregular, lop-sided cone shapes. For more regular shapes, you could place the cone’s origin on a corner of your square and then count squares in two directions up to the length specified. Connect the ends of those two lines to form a triangle, and everything inside is affected.

Finally, you have the cube shape. Most often, a cube can easily be represented on the gird as a simple square on the map. A 20-foot cube effect, like that created by the Faerie Fire spell, marks out a 4×4 square on the grid and effects everything inside that area. The one weird thing to remember is that the point of origin for a cube is anywhere on a face of the cube–that is on the outside of the cube, not inside of it. Most of the time, this doesn’t really matter, but the common exception is the Thunderwave spell. The description for Thunderwave states that the spell creates “a 15-foot cube originating from you,” which most people interpret as meaning a 15-foot square centered on you. However, because the cube’s origin is always on one face of the cube, Thunderwave actually affects creatures in any 3×3 square that is adjacent to you.

Either of these yellow squares are valid areas for Thunderwave

Adjudicating areas of effect can be tough for any DM. Many tables like the more freeform “theater of the mind” experience, but that can also lead to feeling like it’s completely up to the whim of the DM whether that Fireball can affect an entire horde or just one or two goblins. Using a grid makes things a little more concrete, but also presents its own problems. What solutions have you used to quickly and fairly resolve these issues?

Players and Characters

Wafflicious is back in the DM’s seat this week to continue our 5e Cthulhu Mythos adventure. Our players include:

  • JosephusBrown as Anton Illinois (Human Inquisitive Rogue/Fighter), a disgraced archaeology professor who has turned to seeking arcane rituals
  • CleverGuy as Bastian Updelver (Deep Gnome Alchemist Artificer), an eccentric local potionmaker
  • TheHayesCode as Hazel Green (Dhampir Spirits Bard), a flapper, séance MC, and aspiring spiritualist
  • Spiny Creature as Ku (Kenku Twilight Cleric), a local priestess of Bastet, goddess of protection
  • The Wasp as Leah Zann (Tiefling Great Old One Warlock), a professor from Miskatonic University who accepted a deal with Yog Sothoth to get an advantage over her male colleagues
  • The Ugly One with the Jewels as Minty Rocksmasher (Dwarf Berserker Barbarian), survivor of an eldritch accident which decimated her tribe

No game this week!