Aerrastia

Aerrastia was a fictional universe built by Kerry, initially in collaboration with Robert and later in collaboration with Sutton, from late 2018 to early 2020. In Aerrastia, travellers on a magical railway system called the Network could visit their own memories and live in alternate realities that branched off from their personal histories at points where the Network allowed them to explore the implications of having made different decisions. It was also possible to use the Network in special ways to change one's real personal history.

In the context of Glastieven mythology, parallels were noted between Aerrastia and the Mission Cycle. The protagonists of Aerrastia shared their names with the protagonists of the Mission Cycle, and their settings also shared a common origin in the Midnight Hotel stories of 2017, though they had been taken in drastically different directions. It was often called an alternative—specifically, a "Mikaran" or "Lanataic", adjectives meaning related to Kerry and Sutton—version of the Mission Cycle. Sometimes, this meant a so-called Aerrastian Cycle was described as an "apocryphal cycle" of Glastieven mythology, included on the edge of the canon. On other occasions, Aerrastia was labelled as a separate "Lanataic mythology".