Why did Saruman not use fire magic against Treebeard's army?
In The Two Towers Saruman's base at Isengard comes under attack from Treebeard and the Ents. They devastate Saruman's facility. Saruman looks out ineffectually from his tower Orthanc.
Later in The Return of the King (extended edition) Saruman becomes enraged and uses a fireball spell to attack Gandalf The White.
Given that he can cast this kind of spell, why did Saruman not use fire magic to combat the Ents?
Best Answer
Perhaps the fireball only works at close range, and he wanted/needed to stay at the top of the tower (for a better strategic overview, to keep some defense systems running, to inspire his troops)? Perhaps a fireball does damage but isn't capable of setting things on fire unless they're really flammable, and a living tree is not (there might be a lot of liquid flowing through its body)?
You see several Ents in the battle which do catch fire (because of fiery arrows or other non-magic flame), so it's not like his army didn't employ it.
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Why did Saruman not fight the Ents?
All his power was bound up in his devices and slaves. Also, Saruman knew that the Ents could not harm Orthanc itself, so it would probably make more sense to hide in the tower than risk harm by coming out and fighting the Ents in person.What magic can Saruman do?
By far, Saruman's greatest power (and the only one he could retain after the downfall of Isengard), however, is speech. He seems to have had the ability to bend any but the absolute strongest minds to his will, simply by speaking to them.How did the Ents destroy Isengard?
At midnight, the Ents succeeded in destroying the dam, and the river flooded the 'bowl' of Isengard, submerging everything but Orthanc and filling in all the tunnels and holes where the machinery of war had been. The destruction of Isengard was complete, although Saruman was still untouched in the tower.LOTR Extended Edition // 0 - The Death of Saruman
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Answer 2
Saruman makes no effort to defend Isengard
If we examine the scene of the Entish invasion of Isengard, we see that Saruman actually does nothing to muster any defense. He is shown several times just watching the disaster from a balcony on Orthanc.
This may be because he realizes the situation is hopeless
Saruman's army is away at Fort Eorlingas, with only a token crew of Orcs left behind at Isengard. They are hopeless to repel the Ents. Saruman cares nothing for his troops and makes no attempt to lead, organise, or defend them.
The Orc strategy of using fire on the Ents was nullified
We do see an Ent on fire during the battle sequence, but the fires are quenched and the Ent saved when the Ents break the dam.
TL;DR Saruman locks himself in Orthanc with a view to talking his way out later
One of Saruman's greatest weapons is the sorcery of his persuasive voice and his mastery of diplomacy. Any aggression against the Ents makes this less likely to succeed (though he does of course attack Gandalf the White once provoked).
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