Listening to the 'back and forth' there was thought provoking to say the least. I think if the Watcher had indeed devoured Frodo and the Ring with it, Gandalf would have realized that the Watcher would have to go, meaning they would probably try to slay it even if they couldn't save Frodo, which would have been a most perilous turn of events unless Gandalf would use his arts to destroy it, what ever they may be. However, just for arguments sake, if the Watcher was victorious and consumed the Ring I think it would have driven it mad. Or given it some cognitive thought and it would of struck out and possibly grown greater and more evil. Perhaps leaving is lair in the water outside the Gates of Moria and slithering to find more things to devour. It would have become a scourge and definite problem for the Orcs that dwelt near or in the mountain. Eventually they would try to swarm it and destroy it, perhaps eat it and in the process if the Ring were to be found that way then the Orcs would war amongst themselves and since the Orcs belong to Sauron by Lore then the Ring would be on an express to Mordor. Cut! End scene! I'll be in my trailer!
I just re-read that passage in the fellowship of the ring to make sure my next comment was accurate. I saw nothing that implied that the wathcer in the water wanted to devour Frodo. It was apparent that the watcher was drawn to frodo or more likely the ring but I saw no intent to eat him. If he was indeed after the ring then he was to some extent at least intelligent and tactical. If he had taken frodo I believe the remaining 8 members of the fellowship would indeed kill the watcher unless he had more power then it seemed to me. It does seem conceivable to me that the watcher may have been in league with sauron or maybe even Durin's bane. I would most likely say sauron. Maybe he (Sauron) wished to block the path of the fellowship. That is all of course simply speculation though and I have no proof of this. Nor do I know of the watchers true origins.
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But no wizardry nor spell, neither fang nor venom,nor devil's art nor beast-strength, could overthrow Huan of Valinor;
You say: "I have no proof of this." But I say, with your statement you give me much food for thought. At this point in the Fellowship of the Ring, we know that Saruman was in league with the dark powers; so we know that Sauron was putting forth his will; summoning many of his minions to Him by thought alone (including Gollum, who was near Dale or the Long Lake when he heard the call. Then heeding the call he was captured and questioned by Sauron about the Ring). It wouldn't be out of the question that the Ill-will of the Watcher was spurred by "The Call". Although it was the Dwarfs that delved too greedily and too deep stirring the Balrog (Who may have stirred originally by Sauron).
Could it have been that when the Balrog busted up Khazad Dum that he opened a way for the Watcher to escape the depths? It was a water creature, that much we know. Where else about the lands surrounding the Misty Mountains was there so grand a water source that it would call home? Plus someone (either orc or man) would have recorded seeing such an odd creature passing along the low lands before it ascended into the high places of the mountains? Therefore it must have come from the depths of the mountains.
You know, I've never thought of why the watcher was there at that gate. But your ideas about its comings are very interesting to me. I have to agree that its the only solution that makes sense at this time. That it came from the depths of the mountains after Durins bane sturred things up a bit down there
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But no wizardry nor spell, neither fang nor venom,nor devil's art nor beast-strength, could overthrow Huan of Valinor;
This is all very interesting; and I must say the theory reguarding Durin's Bane does make quite a bit of sense. Either way, I applaud Tolkien for all the mysterys in his works, it truly is great storytelling as it allows the reader to have a bit of fun imagining and speculating. He truly was a master.
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"Let's hear about Frodo and the Ring." - Samwise Gamgee
That he was. So many many years after his works and there are still countless fans on forums such as this discusing his art. A great man he must have been!
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But no wizardry nor spell, neither fang nor venom,nor devil's art nor beast-strength, could overthrow Huan of Valinor;