You can also cast Spell Shield and Aura of Guarding on summoned or resurrected creatures.
There are a few boss-type monsters that do not die when you sleep. Someone posted about using the skeleton conjurer from under the warrior's guild in the Dark Forest. It would start summoning on sight of an opponent, eventually amassing an army of skeleton warriors. This made the game way to easy, so the person stopped using it (after getting a screenshot showing a good portion of their min-map filled with the green crosses of skeletons).
