The Death of an Outsider

[Torgoth99]

When an outsider dies on the material plane, what happens to the body?

[hamishspence]

Varies. Fiendish Codex I had a big list of things that could happen when a demon dies on the material plane- body might disappear, might remain, weird things might happen to the body, etc.

[Acanous]

Usually it's played that they vanish like a summoned monster, unless you've done something like Dimensional Anchor'd it before it died.

[KillianHawkeye]

That depends on numerous factors, including: game setting, mood of the DM, type of Outsider, and whether they have been Summoned or Called to the material plane (or have traveled there by other means).

Summoned creatures automatically return to their place of origin upon death. Non-summoned creatures will either leave a corpse like normal creatures or they'll disappear anyway. Fiendish Codex says slain demons reform in the Abyss. IIRC, Fiendish Codex 2 says slain devils rise again in the Nine Hells after a period of 99 years (at which point they usually get demoted or punished somehow). Native Outsiders definitely die like ordinary creatures. Beyond that, there's not too much to go on. Some DMs like Outsiders who vanish or melt away, others let them rot.

[karkus]

Summoned: They return to the exact point that they were originally Summoned from.

Called: They are dead, just as though they were mortals (you can Call Outsiders through the use of Planar Ally or Planar Binding spells).

If they have simply come to the Material Plane of their own accord, such as by Plane Shift, Gate, etc.: This is among the least-explained rules in D&D, as well as the most likely subject of your question. Usually, they reform in a day or so, but are otherwise free to return. If you Dimensionally Anchor/Lock them, they could either a) still disappear, like a Summoned creature, or b) stay there, dead, until the effect is removed, at which time, effect "a" happens (the second one, "b," sounds pretty awesome to me).

If they are Native Outsiders (meaning that they were born on the Material Plane), then they die just as mortals do, so they can be Raised, as well as immune to Banishment effects.

In short, it really depends on what the DM needs/wants.

[Slipperychicken]

AFAIK, Some of them re-form on their native plane, since their souls just go back there.

[KillianHawkeye]

If they are Native Outsiders (meaning that they were born on the Material Plane), then they die just as mortals do, so they can be Raised, as well as immune to Banishment effects.

Minor correction: banishment effects work on any extraplanar creatures regardless of their type. Native Outsiders are material plane creatures, so they can be banished back to the material plane when they are found on other planes.