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Line Spells / Lightning Bolt

Hi Folks,
Quick question. Can a lightning bolt cast effectively act as 10' wide on a square grid? Looking at Xanthar's (p. 87 Diagram 2.6), it essentially looks like this is a way to adjudicate it. Essentially, someone casting a lightning bolt down the grid line so it goes half into both adjoining squares. How do you normally judge this? Thanks.
 

FrogReaver

Explorer
I play more totm. In totm if 2 players are adjacent and you cast lightning bolt it can hit both. As such I’d rule that it’s possible for in grid based play as well.
 

Saelorn

Explorer
Generally speaking, if you cast it right down the line, it should effectively hit 10' wide along its entire length. Depending on the situation, I might give one or both creatures Advantage on the saving throw, since it only clips half of them. If you fire it at any angle other than along the grid, there are going to be places where it covers some squares entirely and other squares by less than half, so be prepared for ad-hoc adjudication.

If you only care about hitting two enemies that are next to each other, but far from you, then you should almost always be able to fire it in such a way that both will be hit.
 
For a 10 foot line, You pick two 5 foot squares in front of you. The lightning bolt follows the path along those two lines.

000000000000000000000000000 (1)
X 000000000000000000000000000 (2)
000000000000000000000000000 (3)

Let's say 'X' is the character and '0' are the grid squares. 1, 2 and 3 are your 3 options for the line of the lightning bolt. You have to choose the line of squares (2) directly in front of you. You then get to choose one of the lines adjacent to (2); either Line (1) or (3).

So, if the dash is the path of the lightning bolt, it can look like this:

00 ------------------------------------- (1)
X ------------------------------------- (2)
000000000000000000000000000000 (3)

or this:

000000000000000000000000000000 (1)
X--------------------------------------- (2)
0- -------------------------------------- (3)

Edit: the formating is a bit messed up, so hopefully, you get the idea

If you look closely at the diagram in Xanthar's, you can see the player chose the line in front of and to the right of the mini.
 
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aco175

Explorer
I'd be inclined to not allow it. I can see players arguing that creatures in the 5ft space do not actually take up the whole square and the bolt should not target the whole 10ft.
 
Wait. Have I misunderstood the question?

Are you saying you want a lightning bolt to target the line down the middle of a 2 adjacent grids? I wouldn't allow that. Choose your line and the bolt goes along fully inside the squares. The diagram in Xanathar's does not show the lightning bolt going down the line. It shows two rows of dice and each die is fully contained inside a square.

-The first two images in diagram 2.6 are of a 5 foot wide 'line effect' on a straight grid angle and then on a diagonal angle.
-The second two images in diagram 2.6 are of a 10 foot wide 'line effect' on a straight grid angle and on a diagonal angle.

It is not showing you 4 ways to adjudicate a 5 foot wide line effect.

Tokens can't finish their movement between squares. If they don't have enough movement to make it to the next square (like if their movement was impeded by terrain and they had 2.5 feet left), they have to stop in the closest square, not half-way between. Spells work the same way.

I thought you were asking how to adjudicate a 10 foot line.
 
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[MENTION=6748898]ad_hoc[/MENTION], I was not assuming anything - this is why I asked the question. However, the previous tokens for the cone above it is showing instances of the same area effect which threw me off. However, that's a good point that it's probably a 10' for the bottom and a 5' wide for the one above it in that diagram. I appreciate the insight.
[MENTION=15882]TaranTheWanderer[/MENTION] - thanks for this. I was actually asking both and your diagram definitely helped clarify this to me!

I appreciate everyone's response to this.
 
[MENTION=15882]TaranTheWanderer[/MENTION] - thanks for this. I was actually asking both and your diagram definitely helped clarify this to me!

I appreciate everyone's response to this.
No problem. And just for clarification's sake: for lightning bolt, since it is only a 5 foot wide effect, you'd only use the two top diagrams to adjudicate the line of effect.

If you had some kind of meta-magic effect that made lightning bolt into a 10 foot wide effect, you could use the bottom two diagrams. (off the top of my head, I can't think of a 10 foot wide line of effect spell...I'm sure there's a few. Blue Dragon's breath, maybe?

edit: Gust of Wind! 10 foot wide, 60 foot Line
 
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Shiroiken

Explorer
I do not force players to follow the guidelines in the DMG for casting spells on a grid. It breaks the verisimilitude for me, as I prefer to play TotM. At one point I actually considered using 2.5 ft squares to allow for such nuance, but unfortunately everyone is already accustomed to 5 ft squares, making the switch too annoying for my players. Instead I created a bunch of templates, and allow them to be used to determine the AoE.

Allowing it does make some abilities stronger, but to offset that I usually grant advantage on saves for those not in a fully affected square. This works both ways, for and against the players, so it hasn't caused any major imbalance.
 

S'mon

Hero
If you insist on casting in between two foes each 5' apart, I guess I'd likely give each a 50% chance of being hit.
 

Oofta

Explorer
The 5 ft square is an abstraction for placement. Some creatures are going to be practically next to each others, others are gong to be more than 5 ft apart. So I'd agree with the 50% chance of hitting someone on either side.
 

Blue

Orcus on a bad day
Lightning bolt is 5' wide. In a 10' corridor there's no problems doing it down the middle with 2 1/2 feet on either side of it. 2.5' is not enough room for a medium or small sized creature (unless they were possibly already squeezing) so it would hit ones on both sides.

That said, there are rules for grid play and a common, oft unconscious, impulse is "snapping" all effects to the grid. So that a 5' line must go down one 5' half of a corridor or another. Mind you that plenty of other spells, especially radius, hit those that are partially in it, so this is a hidden nerf to line (and possibly cone) spells if required.

On the other hand I've played with plenty of DMs over years (and editions) who do not require snapping effects to the grid. The best judge of those I've seen used a cool set of clear plastic spell area templates that you just lay down on the map wherever you want and it's obvious who's in the AoE or not. So even with grids this is not a given.
 
W

WhosDaDungeonMaster

Guest
Hi Folks,
Quick question. Can a lightning bolt cast effectively act as 10' wide on a square grid? Looking at Xanthar's (p. 87 Diagram 2.6), it essentially looks like this is a way to adjudicate it. Essentially, someone casting a lightning bolt down the grid line so it goes half into both adjoining squares. How do you normally judge this? Thanks.
The diagram in Xanthar's shows how it is only supposed to be 5' wide. Likely the diagram you refer to is for the 10' wide effects (the bottom right-hand placement), the one above that is for 5 feet wide. It shows shows this is along the 45 degree diagonal (see Figure 1, only hitting target 2). However, this is rather limiting and you probably don't want to only be able to shoot along diagonals, so there are options you might want to consider:

First is the straight line. Using a ruler, yardstick, or string, you draw a straight line from the origin to the end point. ANY portion of a square that line passes through is affected. In Figure 2, that would be targets 2, 4, and 5. This allows for optimal placement.

The second option is the pattern (Figure 3). Each movement to the right from origin character "T" is allowed 1 square to occupy and must have a common corner point. The pattern must repeat. In this example, the lightning bolt would hit targets 4 and 5.

lightning_bolts.png

Different DMs use other methods, but options such as these are pretty common. Hope that helps.
 
W

WhosDaDungeonMaster

Guest
Lightning bolt is 5' wide. In a 10' corridor there's no problems doing it down the middle with 2 1/2 feet on either side of it. 2.5' is not enough room for a medium or small sized creature (unless they were possibly already squeezing) so it would hit ones on both sides.

That said, there are rules for grid play and a common, oft unconscious, impulse is "snapping" all effects to the grid. So that a 5' line must go down one 5' half of a corridor or another. Mind you that plenty of other spells, especially radius, hit those that are partially in it, so this is a hidden nerf to line (and possibly cone) spells if required.

On the other hand I've played with plenty of DMs over years (and editions) who do not require snapping effects to the grid. The best judge of those I've seen used a cool set of clear plastic spell area templates that you just lay down on the map wherever you want and it's obvious who's in the AoE or not. So even with grids this is not a given.
I've allowed this scenario as well, but inform the player "splitting" the edge along the gridlines will allow enough space (that 2.5 feet on each side), that any medium or smaller target will get advantage on their save. Likewise with cone-effects, things on the far edge might get advantage on those saves. But, that's just how we do it. :)
 
It's a little more trickier on a VTT. If I was on a combat map, it probably wouldn't be a problem as I have templates for this. I may allow it but give those that square isn't more than 3/4 affected advantage on their saving throw. I appreciate the diagrams above [MENTION=6976296]James Grover[/MENTION]!
 
W

WhosDaDungeonMaster

Guest
It's a little more trickier on a VTT. If I was on a combat map, it probably wouldn't be a problem as I have templates for this. I may allow it but give those that square isn't more than 3/4 affected advantage on their saving throw. I appreciate the diagrams above [MENTION=6976296]James Grover[/MENTION]!
No problem. Ruling less than 3/4 coverage advantage is a good way to go if it works for your group.
 

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