Emanation

An Emanation is a type of Area of Effect that extends outward from a point of origin — typically the caster or a creature — in all directions, filling the space within its range. Unlike a Sphere centered on a point you can choose, an Emanation moves with its origin.

Shape and reach:

• An Emanation extends in a specified distance (e.g., 10-foot Emanation) from the origin
• It is a sphere of effect, but it explicitly moves with the source
• The source itself is not typically affected by its own Emanation unless the effect says so
• The Emanation does not extend through walls or Total Cover; it stops at the obstruction (the rule is identical to a Spread for line-of-effect purposes)

Common uses: Auras such as a paladin's Aura of Protection, spells like spirit guardians, and monster effects (a dragon's frightful presence, a lich's aura of decay) are typically Emanations. They distinguish themselves from a one-time-blast AoE (Sphere, Cube, Cone, Line, Cylinder) by persisting and traveling.

Targeting: All creatures within the Emanation are normally affected at the start of their turn or on entering the space, as the effect specifies. A creature that leaves the area is no longer affected. A creature that enters mid-turn is affected immediately (or as the effect dictates).

Contrast: Sphere, Cube, Cone, Line, and Cylinder are other AoE shapes; only Emanation explicitly moves with its source.