What happened to the Cloud Kingdom, or the rest of it?

Honestly, what happened to the Cloud Kingdom? In Dragons Rising we only saw a few islands, compared to what was shown in Possession, which was literally a city, and now it's downgraded to islands? And why aren't the writers of destiny in the library anymore? Now they're outside, and there are even fewer of them compared to before. Did the Merge destroy the Cloud Kingdom or something else? (I've already watched Dragons Rising, but this question still remains.) submitted by ...