# Area

> Kinbarrow modding reference — content tree `4a103dcdb658a75a`, version `0.2.0+main.e011511f4`.

[Effects and mechanisms](https://kinbarrow.com/modding/latest/mechanisms.md)

Used by [Spell](https://kinbarrow.com/modding/latest/spell.md#area), [ClassDef](https://kinbarrow.com/modding/latest/class-def.md#area), [MagicItem](https://kinbarrow.com/modding/latest/magic-item.md#area), [Npc](https://kinbarrow.com/modding/latest/npc.md#area), [FeatDef](https://kinbarrow.com/modding/latest/feat-def.md#area), [RaceDef](https://kinbarrow.com/modding/latest/race-def.md#area), [SubclassDef](https://kinbarrow.com/modding/latest/subclass-def.md#area).

This is a nested shape inside a content file. The catalog explains context validation and links real RON examples.

An area of effect, resolved on the encounter board's 5 ft grid: a sphere centers on the TARGET, a cone/line throws from the CASTER toward it, a burst centers on the caster (thunderwave's "Self (15-foot cube)", radius-approximated on the Chebyshev grid).

<a id="area--sphere"></a>

## Area::Sphere

A sphere of `radius_ft`, centered on the target point (fireball).

| Field | Type | Required | Description |
| --- | --- | --- | --- |
| `radius_ft` | `uint32` | required |  |

<a id="area--cone"></a>

## Area::Cone

A cone of `length_ft`, thrown from the caster toward the target (burning hands).

| Field | Type | Required | Description |
| --- | --- | --- | --- |
| `length_ft` | `uint32` | required |  |

<a id="area--line"></a>

## Area::Line

A line of `length_ft`, thrown from the caster toward the target (lightning bolt).

| Field | Type | Required | Description |
| --- | --- | --- | --- |
| `length_ft` | `uint32` | required |  |

<a id="area--rectangle"></a>

## Area::Rectangle

A directional rectangle with independently authored long and wide dimensions. Placement supplies a near-left corner and a second point choosing its long axis; neither dimension is approximated as a line or sphere.

| Field | Type | Required | Description |
| --- | --- | --- | --- |
| `length_ft` | `uint32` | required |  |
| `width_ft` | `uint32` | required |  |

<a id="area--burst"></a>

## Area::Burst

A burst of `radius_ft` centered on the caster (thunderwave's "Self" cube, radius-approximated on the grid).

| Field | Type | Required | Description |
| --- | --- | --- | --- |
| `radius_ft` | `uint32` | required |  |

<a id="area--emanation"></a>

## Area::Emanation

A radius centered on and including the origin creature. Unlike a burst, an emanation includes its origin and needs no aim point.

| Field | Type | Required | Description |
| --- | --- | --- | --- |
| `radius_ft` | `uint32` | required |  |