I own nothing.
No one really understood why Glorfindel was smiling when he prophesied the ultimate demise of the Witch-King, that he would not be felled by the hands of man. Eärnur certainly wasn't smiling, as in his opinion they could have defeated the Witch-King of Angmar here and now, but Glorfindel paid him no mind.
Glorfindel was always known for being easygoing and cheerful, for keeping a spirit of optimism even in a bad situation. But this was the end of a battle, many of his soldiers were dead, and quite frankly he should not have been smiling. But he was.
The others had not seen what Glorfindel had seen when he made that prediction. He was surrounded by corpses, it was true, but he could not help but grin at the image of the Witch-King being killed by a maiden and what looked like a child.
That image would be enough to sustain him through any bloodbath.