Parallel plane

Parallel planes were planes of existence which existed in parallel with the Prime Material Plane. They were defined by a shared geography, bestiary, and were more easily reached than other planes by inhabitants of the Prime. The parallel planes were created in the days of creation when the Primordials, mighty beings on par with the gods, split the Prime into three parts, finding some parts "too bright" or "too dark." The two parallel planes created were the Plane of Shadow and the Feywild, though the Plane of Shadow later transformed into the Shadowfell.