Well, for now at least, let’s see how much of the day I’ll have off. My idea for enemies-as-weapons is as follows. You control a wizard who has two spells. A fireball which does some direct damage to a creature. And a zombification spell which resurrects bodies of fallen creatures as zombies loyal to their master. The game now has a few areas with creatures of different strength and you are to build up an army of zombies to face the final boss.
The screenshot below is how far I am right now after about 2 hours and also how the final graphics will look. It shows the wizard and some enemy creatures.