Which 3.5 planes are shifting?

[Particle_Man]

Horizon walkers with the shifting ability get an insight bonus to hit and damage outsiders and elementals native to a shifting plane. What are the planes that are shifting (just Limbo and plane of Shadow?) and which outsiders and elementals are native to them (just Slaadi?)?

[Bronk]

Horizon walkers with the shifting ability get an insight bonus to hit and damage outsiders and elementals native to a shifting plane. What are the planes that are shifting (just Limbo and plane of Shadow?) and which outsiders and elementals are native to them (just Slaadi?)?

Since I don't think 'shifting' is a game term when it comes to planes, I guess the list should include anything you could reasonably describe that way. If they'd wanted to use game terms, like pinning the ability to planes with a specific morphic level, they could have.

I agree with the two you listed: Limbo definitely, as it's highly morphic, and Shadow is often described with features that aren't always in the same place. I'd add the Outlands for sure, because the gate towns shift back and forth all the time, and the plane includes the Hinterlands which are ever shifting around, and in general you can get anywhere on the infinite plane in just a few days travel... somehow. Archeron is a bunch of moving cubes, so maybe that one too.

I can't think of any elemental planes that fit the bill right off (although Fire is described as having shifting flame all around), but the ability does mention elementals, so maybe one of the paraelemental planes where forces mingle.