Extra-Planar
From AmtWiki
Extra-Planar
A type of Monster. These creatures are not from our world but another.
Definition
They include angelic creatures, demons, and elementals. Extra- Planar creatures are immune to Death School and Poison. These cannot carry enchantments save for the one used to summon them.
From Dor Un Avathar
These creatures are not from this dimension but another, alien plane of existence. They include Angelics, Demons, and Elementals. Extra-Planar creatures are immune to Death and Poison. They cannot carry enchantments except for the one used tosummon them, if such is the case.