The Dream

Not long after the founding of the Grey Empire, the remaining pureblood grey elves, believing mortals had rendered the world too 'ugly' to tolerate having any sensory experience of it, collectively decided to undergo a procedure they described as 'entering the Dream', which slowly turned them into humanoid plants, finally becoming a full tree without any external sign of consciousness.

It was believed that inside this tree the grey elven soul would keep living, and experience an idyllic dream world filled with the wildest beauty and pleasure imaginable.

However, if parts of the tree were to be cut off, the dream would become less pleasant.

Were the tree to be reduced to a stub, the spirit inside would experience a horrible nightmare, continuously until the tree has regrown a substantial amount of its former size.

During the age of Arúmil's return, a number of these trees temporarily reverted to a semi-humanoid, conscious form in order to help the mortal Wanderer defeat the Emperor again.

Previously, the temporary hybrid creature known as the Grey Elf had been romantically involved with a surviving pureblood grey elf who had been delaying her transformation for thousands of years by forcefully going against her grey elven nature (as she had a minute portion of mortal ancestry, which could influence her nature if she steered her mind in the right direction). When she fell in love, her original nature resurfaced, which triggered the transformation.

An eternity inside the Dream, sublime as it was, would be a torture without her lover.

It's currently unknown whether she participated in the attack on the returned Grey Emperor, but it is plausible since she would feel a lot of hatred towards him for essentially causing the death of her lover. It's also possible that due to being in humanoid form again and experiencing such un-grey elf-like emotions she might be kept from reverting to her tree form. Ironically, while she would finally be freed from her predicament, she would have ended up in a worse situation: still an eternity without her lover, but without all the pleasure and beauty that came in spite of it. Thus she could either decide to leave the past behind her and fully accept her grey elven self, or suffer a tragic destiny (to the discretion of the author!)