In the third Hobbit movie and in the book, the massive army of orcs and goblins from Dol Goldur and Gundabad march on The Lonely Mountain, resulting in the Battle of the Five Armies.
My question is what was the original goal of this force? It is shown several times that Smaug and Sauron were in league together, and that Smaug was presumably waiting for Sauron to gather more strength in order to take over Middle Earth. Sauron wanted the Lonely Mountain both for its strategic position and strength as a fortress, and I assume Smaug was willing to let Sauron use the mountain for that purpose, even if probably wasn't willing to let Sauron have any of his hoard.
So, when Smaug died, Sauron must have had a "oh shit" moment and commanded Azog to go take the Mountain, fast. But if he didn't need that army to take the Lonely Mountain before, what was his target? Azog had a standing army ready to go, so what was it for? The Mirkwood Elves? The Ironhill dwarves? Or just to torch the landscape and turn it into Mordor 2.0?