[CSteefel]

Originally Posted by Raynor

To conclude, while the status of the WK as leader of armies is reinforced time and again before this battle in the books, his show of magic force here is definitely outstanding. To me, the interpretation of added demonic force is obvious.

Thrice he cried. Thrice the great ram boomed. And suddenly upon the last stroke the Gate of Gondor broke. As if stricken by some blasting spell it burst asunder: there was a flash of searing lightning, and the doors tumbled in riven fragments to the ground.

I would agree that this is good evidence of the Witch King's added demonic power. As several people have pointed out above or in other contexts, the Witch King (like the other Nazgul) know when to withdraw when they are overmatched. They held back from Gandalf on Weathertop during the daylight, but then closed on him (all nine) after dark, although Gandalf was able to hold them off. Even Aragorn drove them off.

But by the time the Witch King arrives at the Pelennor Field, he is able to break the Gates of the City and to face Gandalf, unless one interprets his departure to check on the horns of the Rohirrim as actually flight from Gandalf, although this does not seem likely given his challenge to Gandalf

'Old fool!, he said. "old fool! This is my hour. Do you not know Deathe when you see it? Die now and curse in vain!'

Clearly, the Witch King is feeling as if he can stand up to Gandalf, although it is not clear that understands completely that Gandalf's own power has been substantially enhanced.

Otherwise, the Witch King's breaking of the Gates of the City might be seen as similar to Gandalf's sundering of the Bridge at Khazad-dûm with his staff. This in fact succeeded in sending the Balrog into the depths (even if it did not kill him), and only by a combination of skill with his whip (and perhaps a bit of luck) was he able to take Gandalf with him.

So I'd say the Witch King, at least with his added power, would be quite a match for the Balrog, if it came to that...
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