Comes and Bursts out of a Hallway.

[Vali Nepjarson]

In a recent game we weren't entirely sure how certain spell areas would manifest when the origin of that spell is in a hallway, but the area extends outside of the hallway.

As a Nymph-Blooded Sorcerer, I cast my Focus Spell, Blinding Beauty which has a 30-foot come. I was 10 feet into a hallway, aiming into a room with several enemies.

We weren't sure if the area would be entirely funnelled into only a straight line by the hallway, or if the cone would begin spreading from the point of exit of the hallway and create the equivalent of a 20-foot cone at the mouth of the hallway.

It didn't directly come up, but it also made us consider what would happen if someone cast something like Fireball in a hallway, with a portion of its area of effect extending out of the hallway. Would it just create a line of fire shooting straight out of the hallway or something like a half-circle with a radius of however much radius was left in the fireball?

Since the spell was a visual effect, we decided that anyone who could reasonably see could be effected, and that was fine for us, but I would like to know if there is an actual RAW answer.

[Conscious Meat]

The walls would normally block the effect.

Player Core, pp. 426, "Line of Effect" section. As quoted on https://2e.aonprd.com/Rules.aspx?ID=2382

Quote:

When creating an effect, you usually need an unblocked path to the target of a spell, the origin point of an effect's area, or the place where you create something with a spell or other ability. This is called a line of effect. You have line of effect unless a creature is entirely behind a solid physical barrier. Visibility doesn't matter for line of effect, nor do portcullises and other barriers that aren't totally solid. Usually a 1-foot-square gap is enough to maintain a line of effect, though the GM makes the final call.

In an area effect, creatures or targets must have line of effect to the point of origin to be affected. If there's no line of effect between the origin of the area and the target, the effect doesn't apply to that target. For example, if there's a solid wall between the origin of a fireball and a creature that's within the burst radius, the wall blocks the effect—that creature is unaffected by the fireball and doesn't need to attempt a save against it. Likewise, any ongoing effects created by an ability with an area cease to affect anyone who moves outside of the line of effect.

For a cone or burst with the origin in the hallway, that point of origin's line of effect could be blocked by the walls of that hallway.

[SuperBidi]

From strict RAW, you will affect every creature with a cover. So that would look like that:

Quote:

⬜⬜▣▣▣▣▣⬜⬜
⬜⬜▣▣▣▣▣⬜⬜
⬜⬜⬜▣▣▣⬜⬜⬜
⬜⬜⬜▣▣▣⬜⬜⬜
⬜⬛⬛⬛▣⬛⬛⬛⬜
⬜⬛⬛⬛▣⬛⬛⬛⬜
⬜⬛⬛⬛Ⓜ️️️️️️️️️️️️️️️️️️️️️️⬛⬛⬛⬜

I hope the drawing is clear. M is the caster and the cone goes up. So it's neither a line nor a cone that starts at the point of exit, it's just calculating line of effects from the point of origin of the cone to the enemy.

For a burst, it's a bit more complicated as bursts are not aimed at squares but at corners. Which generates a weird area:

Quote:

⬜⬜▣▣▣⬜⬜⬜⬜
⬜⬜▣▣▣⬜⬜⬜⬜
⬜⬜⬜▣▣⬜⬜⬜⬜
⬜⬜⬜▣▣⬜⬜⬜⬜
⬜⬛⬛⬛▣⬛⬛⬛⬜
⬜⬛⬛⬛▣⬛⬛⬛⬜
⬜⬛⬛⬛↗⬛⬛⬛⬜

In that case, the point of origin is the top right corner shown by the arrow.

[Farien]

From the title, I was hoping we were talking about the Kool-aid Man.

[SuperParkourio]

I played as the Kool-aid Man in a 5e one shot. My GM and I gave him an adamantine halberd and Siege Monster.

[Cordell Kintner]

Basically, yes the cone would spread into the room. To make it easy, just calculate a cone from the choke point to where the cone normally ends, so with a 30ft cone it would cut it down to a 20ft cone.