Nature of Mares
The following is a discussion of the nature of mares and their essences. This research was done by request of Dreamwright Yog-ka, in fulfillment of a quest for power.
The Dream is a realm where the mind takes precedence over the physical form. The physical Avatar which a dreamer presents to the world is formed through mental strength -- Dreamsoul -- out of the surrounding material of the dream. The nature of the Dream is chaotic, and we dreamers are beings of order. Although the First Dreamers must have formed their Avatars out of the chaos which surrounded them, that task requires immense mental power. It is easier for a Dreamer to form an Avatar in a peaceful and ordered environment, such as that of a Sanctuary. All of this follows directly from the histories. But what of the Mares? They too form Avatars in a sense, though theirs are different from our own. The mares are creatures of chaos -- they came from outside the order of the city of Underlight. This fact is documented in the history of the Nightmare Wars, and several elder dreamers (Balthiir, for example) have clear memories of the entry of the mares into the city. Since the mares are creatures of chaos, it makes sense to assume that while they also form their avatars from the surrounding material, their avatars are formed from chaos rather than order. Indeed, this would explain why mares cannot enter the sanctuaries... just as a dreamer's avatar would likely be pulled apart if he or she left the city and stepped into chaos.
What is essence? Many different theories exist on this point, but most are variants of a single idea. When a dreamer (or a mare) creates an avatar, the individual invests a part of himself in that avatar -- a bit of his own mind is combined with material from the surrounding dreamstate. When the avatar is collapsed, this bit of soul is compressed, along with the remains of the material used to create the avatar, into the essence. This explains the loss of experience when a dreamer is collapsed -- that experience resided in the bit of his or her soul invested in the avatar.
A few theorists would claim that the mare's essence is in fact the whole of the mare's spirit. I reject this theory. It has been observed that after a mare is collapsed, even if the essence is taken, a new mare reappears in the same location shortly thereafter. One could claim that this is a coincidence -- a different mare taking the place of the first. But since mares cannot pass the portals, and no one has ever seen two mares (other than darkmares) in the same place... it seems more likely that the same mare has simply formed a new avatar.
So what happens when essence is imprisoned or banished? The answer to this question depends on the exact nature of the mares, on which there are many theories. My own belief is that mares are like animals -- beings which roam the dream much like we do. In this case, once the essence is removed from the mare, the fate of the essence makes little difference. This would mirror the effect of essence on a dreamer -- though losing the essence is painful, once it is lost, the fate of the essence is irrelevant.
The other major theory on the nature of mares suggests that the mares are somehow formed from the souls of humans, either dreamers or unawakened. If this is the case, it might stand to reason that by either imprisoning or banishing the essence, a part of the human soul would be somehow restored. However, I have found no evidence to this effect. The war against mares pursued by such houses as House Calenture and the Dreamers of Light appears to have no direct effect on humans in the waking world, humans in the dream, or even the mare population. This lack of evidence is insufficient to reject the theory... but it seems more reasonable to assume the mares are independent beings unless such evidence surfaces.
A brief mention of the dark mares for completeness here: it seems clear to all who have observed dark mares that they are fully sentient. They attack in groups, focus their assaults against specific targets... they can use arts as dreamers do... and they have even been observed to respond to English language pleas for peace. These facts would indicate that each dark mare has a single unified soul, and is not some conglomerate of souls of the unawakened. It is my belief that the dark mares are a combination of dreamer and mare, created by the Entropy Coalition in an attempt to make dreamers immune to dreamstrike. Since such a creature cannot be truly at home in Underlight or the surrounding Chaos, they wander about, angry for what has been done to them, and seeking vengeance. My evidence for this belief is beyond the scope of this document, but I will be happy to present it if the interest exists.
In conclusion: Mares form avatars from their own souls and a bit of Chaos, just as we form avatars from our souls and a bit of Order. On collapse, a mare leaves behind a "soulsphere" which we cannot detect, along with an essence. The essence contains the remains of the avatar, along with a bit of the soul of the mare... however, once the essence is detached from the mare, its fate is irrelevant (much the same as when essence is detached from a dreamer). As soon as all dreamers have left the area, the defeated mare forms a new avatar from the surrounding Chaos.
The author would like to thank all those dreamers who offered insight into this matter. In particular, she would like to thank Wraith of the Dreamers of Light, A'Lan Shanik of the Order of the Sable Moon, and Luinitari of the [[Order of the Sable Moon]].