Dawn goes into a coma, because she was The Key, and has a link to the Earth, which is crumbling because of the supernova Hellmouth in Cleveland, and the Hellgods who are breaking through the barrier. Willow also seems to go into a coma, but is somehow woken up by a kiss from her lover, Kennedy when she, Faith and Robin are called back to Rome, because of the non-ending battle in deserted Cleveland.
