Nazgûl Theme

[Nufaciel]

I have to go with Eowyn and Merry also, because of what was said above, and this quote, in the same chapter:

So passed the sword of the Barrow-downs, work of Westernesse. But glad would he have been to know its fate who wrought it slowly long ago in the North-Kingdom when the Dunedain were young, and chief among their foes was the dread realm of Angmar and its sorcerer king. No other blade, not though mightier hands had wielded it, would have dealt that foe a wound so bitter, cleaving the undead flesh, breaking the spell that knit his unseen sinews to his will

I think this proves that Merry had a very great deal to do with the Witch-king's death. Eowyn would have never defeated him without Merry.