Great Magical Awakening

A powerful event some 6000 years ago, that caused a massive shift with in the multiverse. Specifically some material planes collided with each other creating new material planes, and transplanting people. This led to what is now Aushudore, but it does seem that other material planes should be reachable from this plane.
In addition to the chaos caused on the material planes, the outerplanes and gods saw a great change with some dying or losing power. It has been shown that each outplane has a single material plane it is connected to, but that may not have been the case before this.
But moving between planes, where material to material or material to outer has proven very difficulty since this event.