Sunny remembered the first time he went all the way to the northern boundary of the Chained Isles vividly. Back then, it had taken Cassie and him around a month to reach the Night Temple from the Sanctuary of Noctis.
The Southern Island was further away from the Hollow Mountains than the Sanctuary — and yet, Sunny made the journey in under a week. Even then, it had only taken him that long because he was taking his sweet time.
He did not need to traverse the heavenly chains to get from one island to the other anymore — instead, he simply turned into a crow and flew north, landing from time to time to rest or take a look at something peculiar.
The Crushing was of no issue because he could escape it at any time with Shadow Step. The Nightmare Creatures of the Chained Isles were too weak to pose a serious threat to him, at least as long as he stayed alert. Most simply fled, frightened by his dark presence.