[diamond6]

So even though it was Elrond who told him to use the army of the dead to go to battle, Gandalf was the one had the original idea?

Sorry if this is a lame question.

[Corin Stormhands]

So even though it was Elrond who told him to use the army of the dead to go to battle, Gandalf was the one had the original idea?

Not so much Gandalf's idea as it was Aragron's destiny, which Gandalf, Eldrond and Aragorn would have known.