Area effect spells [Archive] - Wizards Community

Area effect spells [Archive] - Wizards Community

Post/Author/DateTime Post
Jermin
07-01-07, 04:12 AM If I use an area effect spell on a hallway (for example) and the spell has enought size to cover the whole hallway BUT the hallway is not strait (it has a turn to the left, for example) would the spell cover it anyways?
kjenks
07-01-07, 08:04 AM There are different categories of area spells, including burst and spread spells. This should answer your question:

SRD
===
Area: Some spells affect an area. Sometimes a spell description specifies a specially defined area, but usually an area falls into one of the categories defined below.

Regardless of the shape of the area, you select the point where the spell originates, but otherwise you don’t control which creatures or objects the spell affects. The point of origin of a spell is always a grid intersection. When determining whether a given creature is within the area of a spell, count out the distance from the point of origin in squares just as you do when moving a character or when determining the range for a ranged attack. The only difference is that instead of counting from the center of one square to the center of the next, you count from intersection to intersection.

You can count diagonally across a square, but remember that every second diagonal counts as 2 squares of distance. If the far edge of a square is within the spell’s area, anything within that square is within the spell’s area. If the spell’s area only touches the near edge of a square, however, anything within that square is unaffected by the spell.

Burst, Emanation, or Spread: Most spells that affect an area function as a burst, an emanation, or a spread. In each case, you select the spell’s point of origin and measure its effect from that point.

A burst spell affects whatever it catches in its area, even including creatures that you can’t see. It can’t affect creatures with total cover from its point of origin (in other words, its effects don’t extend around corners). The default shape for a burst effect is a sphere, but some burst spells are specifically described as cone-shaped. A burst’s area defines how far from the point of origin the spell’s effect extends.

An emanation spell functions like a burst spell, except that the effect continues to radiate from the point of origin for the duration of the spell. Most emanations are cones or spheres.

A spread spell spreads out like a burst but can turn corners. You select the point of origin, and the spell spreads out a given distance in all directions. Figure the area the spell effect fills by taking into account any turns the spell effect takes.

Cone, Cylinder, Line, or Sphere: Most spells that affect an area have a particular shape, such as a cone, cylinder, line, or sphere.

A cone-shaped spell shoots away from you in a quarter-circle in the direction you designate. It starts from any corner of your square and widens out as it goes. Most cones are either bursts or emanations (see above), and thus won’t go around corners.

When casting a cylinder-shaped spell, you select the spell’s point of origin. This point is the center of a horizontal circle, and the spell shoots down from the circle, filling a cylinder. A cylinder-shaped spell ignores any obstructions within its area.

A line-shaped spell shoots away from you in a line in the direction you designate. It starts from any corner of your square and extends to the limit of its range or until it strikes a barrier that blocks line of effect. A line-shaped spell affects all creatures in squares that the line passes through.

A sphere-shaped spell expands from its point of origin to fill a spherical area. Spheres may be bursts, emanations, or spreads.

Creatures: A spell with this kind of area affects creatures directly (like a targeted spell), but it affects all creatures in an area of some kind rather than individual creatures you select. The area might be a spherical burst , a cone-shaped burst, or some other shape.

Many spells affect “living creatures,” which means all creatures other than constructs and undead. Creatures in the spell’s area that are not of the appropriate type do not count against the creatures affected.

Objects: A spell with this kind of area affects objects within an area you select (as Creatures, but affecting objects instead).

Other: A spell can have a unique area, as defined in its description.

(S) Shapeable: If an Area or Effect entry ends with “(S),” you can shape the spell. A shaped effect or area can have no dimension smaller than 10 feet. Many effects or areas are given as cubes to make it easy to model irregular shapes. Three-dimensional volumes are most often needed to define aerial or underwater effects and areas.
===
Jermin
07-01-07, 08:30 AM Wow... long answer, thanks, I'll read'em all and see if it answers my question.

Thanks!
Nom
07-01-07, 10:05 AM If I use an area effect spell on a hallway (for example) and the spell has enought size to cover the whole hallway BUT the hallway is not strait (it has a turn to the left, for example) would the spell cover it anyways?Most area spells are affected by "line of effect". The exceptions are "spreads", "cylinders" and shapeable spells (typically some number of 10 ft. cubes).

Spreads, such as fireball, can turn corners up to their maximum range. Note that you count the path the spell must travel, not as if the obstruction was not there.

Cylinders drop down from above, ignoring obstructions in the way. The wording ("obstructions") suggests to me that this applies to things without tops or other holes, not completely sealed-off areas.

Shapeable spells of cubes can be arranged into any shape as long as no dimension is less than 10 ft.. Implicitly, the effect must be contiguous somehow. It's not clear whether you must have LoE to all cubes. I rule that you must have at least some LoE to each, though the rest of the cube can extend around the corner.

Post/Author/DateTime	Post
Jermin 07-01-07, 04:12 AM	If I use an area effect spell on a hallway (for example) and the spell has enought size to cover the whole hallway BUT the hallway is not strait (it has a turn to the left, for example) would the spell cover it anyways?
kjenks 07-01-07, 08:04 AM	There are different categories of area spells, including burst and spread spells. This should answer your question: SRD === Area: Some spells affect an area. Sometimes a spell description specifies a specially defined area, but usually an area falls into one of the categories defined below. Regardless of the shape of the area, you select the point where the spell originates, but otherwise you don’t control which creatures or objects the spell affects. The point of origin of a spell is always a grid intersection. When determining whether a given creature is within the area of a spell, count out the distance from the point of origin in squares just as you do when moving a character or when determining the range for a ranged attack. The only difference is that instead of counting from the center of one square to the center of the next, you count from intersection to intersection. You can count diagonally across a square, but remember that every second diagonal counts as 2 squares of distance. If the far edge of a square is within the spell’s area, anything within that square is within the spell’s area. If the spell’s area only touches the near edge of a square, however, anything within that square is unaffected by the spell. Burst, Emanation, or Spread: Most spells that affect an area function as a burst, an emanation, or a spread. In each case, you select the spell’s point of origin and measure its effect from that point. A burst spell affects whatever it catches in its area, even including creatures that you can’t see. It can’t affect creatures with total cover from its point of origin (in other words, its effects don’t extend around corners). The default shape for a burst effect is a sphere, but some burst spells are specifically described as cone-shaped. A burst’s area defines how far from the point of origin the spell’s effect extends. An emanation spell functions like a burst spell, except that the effect continues to radiate from the point of origin for the duration of the spell. Most emanations are cones or spheres. A spread spell spreads out like a burst but can turn corners. You select the point of origin, and the spell spreads out a given distance in all directions. Figure the area the spell effect fills by taking into account any turns the spell effect takes. Cone, Cylinder, Line, or Sphere: Most spells that affect an area have a particular shape, such as a cone, cylinder, line, or sphere. A cone-shaped spell shoots away from you in a quarter-circle in the direction you designate. It starts from any corner of your square and widens out as it goes. Most cones are either bursts or emanations (see above), and thus won’t go around corners. When casting a cylinder-shaped spell, you select the spell’s point of origin. This point is the center of a horizontal circle, and the spell shoots down from the circle, filling a cylinder. A cylinder-shaped spell ignores any obstructions within its area. A line-shaped spell shoots away from you in a line in the direction you designate. It starts from any corner of your square and extends to the limit of its range or until it strikes a barrier that blocks line of effect. A line-shaped spell affects all creatures in squares that the line passes through. A sphere-shaped spell expands from its point of origin to fill a spherical area. Spheres may be bursts, emanations, or spreads. Creatures: A spell with this kind of area affects creatures directly (like a targeted spell), but it affects all creatures in an area of some kind rather than individual creatures you select. The area might be a spherical burst , a cone-shaped burst, or some other shape. Many spells affect “living creatures,” which means all creatures other than constructs and undead. Creatures in the spell’s area that are not of the appropriate type do not count against the creatures affected. Objects: A spell with this kind of area affects objects within an area you select (as Creatures, but affecting objects instead). Other: A spell can have a unique area, as defined in its description. (S) Shapeable: If an Area or Effect entry ends with “(S),” you can shape the spell. A shaped effect or area can have no dimension smaller than 10 feet. Many effects or areas are given as cubes to make it easy to model irregular shapes. Three-dimensional volumes are most often needed to define aerial or underwater effects and areas. ===
Jermin 07-01-07, 08:30 AM	Wow... long answer, thanks, I'll read'em all and see if it answers my question. Thanks!
Nom 07-01-07, 10:05 AM	If I use an area effect spell on a hallway (for example) and the spell has enought size to cover the whole hallway BUT the hallway is not strait (it has a turn to the left, for example) would the spell cover it anyways?Most area spells are affected by "line of effect". The exceptions are "spreads", "cylinders" and shapeable spells (typically some number of 10 ft. cubes). Spreads, such as fireball, can turn corners up to their maximum range. Note that you count the path the spell must travel, not as if the obstruction was not there. Cylinders drop down from above, ignoring obstructions in the way. The wording ("obstructions") suggests to me that this applies to things without tops or other holes, not completely sealed-off areas. Shapeable spells of cubes can be arranged into any shape as long as no dimension is less than 10 ft.. Implicitly, the effect must be contiguous somehow. It's not clear whether you must have LoE to all cubes. I rule that you must have at least some LoE to each, though the rest of the cube can extend around the corner.