The Black Rider flung back his hood, and behold! he had a kingly crown; and yet upon no head visible was it set.

I remember the chills I got when I read it for the first time.

I’ll be mad till my last breath at Peter Jackson for not including this in the movies.

The sense is that Gandalf seemed too powerful and the director decided to humble him a bit to add tension.

The answer is pretty simple:

Peter Jackson isn’t nearly as good at telling a consistent story as Tolkien was. This scene isn’t in the books.

Have to watch the Rankin Bass version for that!

I wouldn’t say that. I’d say he did a great job adapting text to a visual medium. In the text just having the sword light on fire in preparation works. When you see it played out, everyone is going to ask why he didn’t take a swing before leaving.

This is exactly what the previous comment is saying. Jackson changed stuff for the movies to cater to mainstream movie audience expectations, at the cost of the worldbuilding and lore.

Maybe having a guy that’s totally invulnerable to the most powerful bad guys is actually not great world building in the first place.

Maybe having a guy that’s totally invulnerable to the most powerful bad guys is actually not great world building in the first place.

He’s not at all invulnerable, in the book they were about to throw down and the Witch King was pretty confident about his chances. Also Gandalf literally gets killed by the Balrog. And beaten and imprisoned by Saruman.

well mostly it’s explained by the fact that it didn’t happen.

"In rode the Lord of the Nazgûl, under the archway that no enemy ever yet had passed, and all fled before his face.

All save one. There waiting, silent and still in the space before the Gate, sat Gandalf upon Shadowfax: Shadowfax who alone among the free horses of the earth endured the terror, unmoving, steadfast as a graven image in Rath Dínen.

‘You cannot enter here,’ said Gandalf, and the huge shadow halted. ‘Go back to the abyss prepared for you! Go back! Fall into the nothingness that awaits you and your Master. Go!’

The Black Rider flung back his hood, and behold! he had a kingly crown; and yet upon no head visible was it set. The red fires shone between it and the mantled shoulders vast and dark. From a mouth unseen there came a deadly laughter.

‘Old fool!’ he said. ‘Old fool! This is my hour. Do you not know Death when you see it? Die now and curse in vain!’ And with that he lifted high his sword and flames ran down the blade.

Gandalf did not move."

and then the Rohirrim arrive and the Rider leaves.

Yes pre-super Saiyan Gandalf is weaker.

He’s not at all invulnerable, in the book they were about to throw down and the Witch King was pretty confident about his chances. Also Gandalf literally gets killed by the Balrog. And beaten and imprisoned by Saruman.

He literally is not a man.

The Witch King was still gonna go him.

Maybe having a guy that’s totally invulnerable to the most powerful bad guys is actually not great world building in the first place.

The Witch-King can fight a wizard for the same reason elves can fight and kill the greatest dragons and balrogs themselves. Binding creatures of spirit into physical form both weakens them and makes them vulnerable to other creatures built of both natures. If anything, as a wraith, he has an advantage in Tolkien rules.

That the Witch King is the equal of a balrog/Maia is not a stretch… Gandalf bring afraid of him even if he is a threat is the stretch, but I’d also argue that’s not being shown in the scene.

That’s the thing though, it’s not invulnerability, it’s, for lack of a better term, will realized as magic.

In Moria,

"…Gandalf stood firm. ‘You cannot pass,’ he said. The orcs stood still, and a dead silence fell. ‘I am a servant of the Secret Fire, wielder of the flame of Anor. You cannot pass. The dark fire will not avail you, flame of Udûn. Go back to the Shadow! You cannot pass.’

This is an invocation - You cannot pass, I am a Maia of Eru, wielder of Narya, Morgoth is gone, Balrog, You cannot pass - and he does, indeed, not pass.

At Gondor, the actual fight starts earlier:

For yet another weapon, […] the Lord of the Dark Tower had: dread and despair. The Nazgul came again, […] More unbearable they became, not less, at each new cry. At length even the stout-hearted would fling themselves to the ground as the hidden menace passed over them, […] and they thought no more of war; but only of hiding and of crawling, and of death.

And so,

So it was that Gandalf took command […] Wherever he came men’s hearts would lift again, and the winged shadows pass from memory. […] And yet – when they had gone, the shadows closed on men again

And, finally,

Spoiler

Fall into the nothingness that awaits you and your Master. Go!’” The Witch-King responds: “‘Old fool! This is my hour. Do you not know Death when you see it? Die now and curse in vain!’” and lifts his sword to strike, and then: “Gandalf did not move. […] a cock crowed. Shrill and clear he crowed, recking nothing of wizardry or war […] And as if in answer there came from far away another note. Horns, horns, horns. […] The darkness was breaking too soon, before the date that his Master had set for it: […] he left the Gate and vanished.”

The night assault was driven by the ringwraith terror. Gandalf doesn’t confront the Witch King physically, he denies his terror, and denies him entry, and when he, unwisely, forces a confrontation, his whole spell folds like a cheap suit.

LotR is running Pathfinder 2e under the hood, by the sounds of it, using Proficiency Without Level.