Watching the travesty that was the Battle of Winterfell has me convinced that about 500 Malazan marines could probably knock over all of Westeros even without Moranth munitions or a High Mage backing them.
I seriously cannot get over how bad the battle tactics for that episode were.
"OK, so first, we all set up in front of our trenches, right. And then, we put the trebuchets as close as we can to the front line, so that the enemy can capture them and turn them on Winterfell without having to risk their dragon. And then we initiate battle with a charge by the Dothraki who, when I last checked were light calvalry. Support? No, they won't need it. Then we will undertake a disorganized retreat to the gates without preparing a rearguard and take sanctuary. In the crypt. When fighting a necromancer."
This is about the point someone should have slit both Dany and Jon Snow's throats and taken command. But alas...