The Merellian is the expansive forest region that follows the equator of the Auldensphere. With the most variety among its indigenous fauna and flora, in can be both beautiful and dangerous. Regions to the North have the default spelling considered normal, though some summer towns spell it Merrelian which angers scribes greatly.
This land wraps all the way around the Auld, with natural borders to many other large regions (the largest being the expansive parallel with The Lea). Plenty of water access can be found in The Merellian, though no one body of water crosses from one hemisphere to the other. This makes is a natural barrier between North and South on the Auld, which explains the difference in developing cultures.
(It may also be a kind of spiritual dampener explaining why gods retain power more to the North or South, though this has yet to be proven the case.)
It has been noted the evolution of plants and animals adapting to environments has rapidly progressed in this area and continues to on a constant basis, with so many animals competing and a thriving plant life.
There are many tribes within the forests and jungles that change with their surroundings while keeping their old beliefs and gods from old times that have grown strong with wisdom of the land.