BTDubs,
If this is for your DFA WRT your other thread, the one about massive amounts of undeaders, I got some grim news. All of the Breath Effects that change your breath into something other than damage all require a Fort save.
Bolded for emphasis. Slow Breath, Enfeebling Breath, Sleep Breath, Paralyzing Breath...none of these work on undead because they allow fort saves, do not affect objects, and are not harmless.
So...bummer. I found that one out the hard way when I made a DFA character for Expedition to Castle Ravenloft.