
Saker |

Since they're made of air I assume they can pass through things like someone in gaseous form, but there is no mention of that.
What I'm wanting to do is create a whirlwind and bang creatures against a force cage by passing through it. It'll just do slam damage and drop them, but I was wondering if that was possible.

Saker |

So, it can't pass through a force cage even in whirlwind form? The way I see whirlwind is you're an air swarm. The fact that you don't provoke AoO and can freely pass through enemy squares like a swarm means that you're insubstantial, but not incorporeal like gaseous form. The limits in this form seem to confirm that, but don't actually say it.