lemeres |
Well, they have the extraplanar subtype. But no, they do not appear to have the subtypes associated with the list rangers use.
Although, looking at it, there are in fact evolutions that can change that. Champions of Purity has the Celestial Appearance evo, which basically allows it to act like a celestial for this kind of purpose (ie. favored enemy: outsider [good]). But that is entirely optional, and it is mostly something to take if you want spell resistance against evil spells and spells by evil creatures.
LazarX |
Eidolons aren't your general outsiders. They're kind of a mashup between Outsider and Familliar.
In other words however, you're exactly right. But then again, summoners however are wonderfully vulnerable to bane and favored enemy, and if you take them out, the eidolon is gone.