So I agree with everyone who said he probably wouldn't have used Dementors. If he had, they wouldn't have been used ever again to guard the prison. I like the idea of Voldemort not being able to cast a patronus, but could his happy memory being killing someone? It's a scary thought, but it seems to fit Voldemort. I agree that I'm pretty sure he used Inferi, probably at least a few giants (I kept wanting to type dragons), werewolves. Like everyone else, I'm not sure what Hags do or if ghosts could exactly help him or would even go to his side. Trolls are kind of stupid, but he may have used them for somethings (though i'm not sure what). Some Vampires probably went to his side because I feel like they would be even more feared than werewolves because they are dangerous all the time, not just during a full moon. But also at this time Voldemort had many more Death Eaters. He may not have needed those creature reinforcements like he did in the second war where actual D.E numbers were lower.