Three times Lórien had been assailed from Dol Guldur, but besides the valour of the elven people of that land, the power that dwelt there was too great for any to overcome, unless Sauron had come there himself.
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Appendix B
That this would prove to be not far from the hated land of Lórien seemed to [the Witch-King] not unlikely, if it was not indeed within the fences of Galadriel. But the power of the White Ring he would not defy, nor enter yet into Lórien.
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UT; The Hunt for the Ring
The chief power (of all the rings alike) was the prevention or slowing of decay (i.e. 'change' viewed as a regrettable thing), the preservation of what is desired or loved, or its semblance – this is more or less an Elvish motive. But also they enhanced the natural powers of a possessor – thus approaching 'magic', a motive easily corruptible into evil, a lust for domination.
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concerning that the Three Rings granted no new powers to fight with, but only increased what the weilder already was capable of, Letter 131
...for Galadriel also was gone and Lorien was withering.
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about Arwen in the Fourth Age, HoME 12
(...) Galadriel was the greatest of the Noldor, except Fëanor maybe, though she was wiser than he, and her wisdom increased with the long years. ... she grew to be tall beyond the measure even of the women of the Noldor; she was strong of body, mind, and will, a match for both the loremasters and the athletes of the Eldar in the days of their youth.
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UT; History of Celeborn and Galadriel
These two kinsfolk, the greatest of the Eldar of Valinor, were unfriends for ever.
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Fëanor and Galadriel, HoME 12