Ravenheart was not undefended, of course.
However, every Saint of the Song Domain was out there, on the battlefield — and even if some of them could return to the seat of the Queen's power in mere minutes by traversing the waking world, they had not done so yet.
Perhaps something that prevented them from returning was happening in Godgrave at the moment. The news Morgan received from the battlefront was usually a few days old, and if Cassia was involved, Nightingale could very well be better informed about the current situation now than she was.
The moment of attack would not have been chosen randomly.
In any case, what met them at the gates of the magnificent black palace was a force consisting of mere Awakened warriors led by Ascended commanders — much like the rear garrisons that had protected Rivergate and Bastion before Morgan and her six Saints… formerly her Saints, rather… showed up.
And the Queen's puppets, of course.
