Although the Elves of Morn Sigil can call upon the vast powers of V'soul's servants, the weavers, there are limits to how, and how much, they can call upon them. The weavers are absolutely literal beings: they do exactly what they are asked to do, no more and no less. They do not speak at all, only nod "yes" or "no" in answer to questions. They answer questions literally, and will not answer ambiguous questions. They will sometimes answer direct questions by showing images in the mirrors of Limbo, but those images are often fairly cryptic. They do not "volunteer information" of any sort to anyone except V'soul, and he is the only one who can contact them from any place outside his Castle.
For reasons of their own, the weavers "altered" Duathir, Elenbarathi and Crist-Erui, giving them the elemental powers of Air, Water, and Earth to balance V'soul's Fire. No explanation has been given of what was done, or why, or of how to use those powers. Therefore the Morn Sigil Clan must discover them and learn how to wield them by trial and error. Since the weavers do not expect the culmination of their Working for at least a hundred thousand years, the abilities are emerging slowly, as their wielders become capable of handling them.
The souls of the three are bound to the Castle of Platinum, in the same manner that V'soul's is, and will be instantly drawn there if they are killed or their souls are otherwise separated from their bodies. The exception to this is that if Crist-Erui were to die while Duathir was in his wraith-form, the soul of both of them would be drawn into the death-realms instead.
Duathir's wraith-abilities are an inadvertent result of his magickal interrogation by the weavers when he was their prisoner... in his attempt to defend himself from their assault on his mind and spirit, he bonded too closely with the death-warrior that shared his being at that time, and his soul was permanently scarred thereby. There is nothing (short of intervention by a major God) that can amend this, and because of it, his soul can never be fully rejoined with Crist-Erui's. Also because of that scarring, he is more than usually susceptible to the Limbo-sickness that affects most beings who spend much time there, and becomes ill when he stays too long at V'soul's house.
Crist-Erui's body was magickally "cloned" by the weavers from the pattern of the original, which is now Duathir's. Therefore, he is not subject to the Limbo-sickness at all, and is practically immune to any magick that does not have its source in Limbo.
Elen is also immune to the Limbo-sickness, having gone through it and recovered. Her soul was destroyed by the magickal backlash that came about as a result of the melding of the Limbo forces with the magicks of the death-realms and her own Elvish spirit-power. However, the pattern of it had been preserved in her enchanted harp, and the weavers reconstructed it. Her magick had been akin to theirs in some ways to start with; they made it more so... thus she is able to join magickally with them in a limited fashion, without having her soul devoured by them, because it is of the same substance as theirs. They appear to regard her as part adopted child, part interesting experiment, and part consort to their unpredictable God, but it is impossible even for V'soul to ever know what they really think about anything.
The weavers built and maintain the treehouse at Morn Sigil. They will make any changes requested to Morn Sigil, but will not change any other place nor do anything to any living being on the Prime Material Plane without V'soul's direct order. If asked, they will fetch things that have no owner from the Prime, but they will not take anything that belongs to someone.
They can make anything (except souls), and anything they make is made flawlessly, but they do not put enchantment on what they make, unless they are specifically told to do so, and in that case they must be specifically told how it is to be done. Since V'soul has forbidden them to cause major magickal changes without first consulting him, there is a serious limit to how much they are willing to do.
The Runes of Return only travel to V'soul's Castle. Anybody who had one and knew the key-word could get there, but the weavers would immediately detain an unauthorized person until V'soul gave other orders (and V'soul is not home to give orders most of the time, so it could be a long wait). The Runes will take the ones to whom they were given from V'soul's Castle to any unwarded place on the Prime Material Plane. Anything the wearer is wearing or holding is also transported... any person the wearer is holding on to is transported; persons holding on to the wearer are NOT transported (in other words, the wearer can only take two people along at a time, and enemies trying to hold on would be left behind.)
The mirrors of Limbo will show any unwarded place on the Prime Material Plane, past or present. Again, a specific place or person must be named, or a specific time if the past is to be viewed. Only V'soul can use them to see places not on the Prime Material Plane.