What creatures and generic NPCs can be reanimated with each of the 'Conjuration - Reanimate' spells?
Solution 1:
Time for more Skyrim Science!
So while I don't have a full answer to your question just yet, I do have some preliminary results.
I've been peeking around in the Skyrim Creation kit, looking at the spell effects for the five spells you list above. For instance:
The highest level reanimate spell has a magnitude of 40.
This is similar to how the master level frenzy spell, Mayhem, is set up, though it's magnitude is 25. This becomes relevant as soon as we read the effect's description:
Creatures and people up to level 25 will attack anyone nearby for 60 seconds
We've documented the frenzy effect over here already, so I think we can safely assume that if Reanimate works similarly (and there's no real reason it shouldn't), the magnitude of the spell effect correlates precisely with the maximum level corpse that can be raised.
That gives us this list:
Raise Zombie - up to level 6 creatures
Reanimate Corpse - up to level 13 creatures
Revenant - up to level 21 creatures
Dread Zombie - up to level 30 creatures
Dead Thrall - up to level 40 creatures
Which gives us an obvious series for our curve.
Double-casting conjuration spells increases the duration, not the effect, so that won't help against higher level enemies, but the Necromage perk will.
As to what level are which creatures, the first thing to realize is that certain creatures (i.e., Dragons, Giants, and Dwemer Automatons) simply cannot be reanimated.
That said here's as good a list as I can manage. If you don't see an NPC on here, it's most likely because they can be found at multiple levels. Creatures are listed under the minimum required spell to reanimate them:
Raise Zombie (up to 6):
- Bandit
- Bandit Outlaw
- Dremora Churl
- Forsworn
- Forsworn Forager
- Forsworn Shaman
- Vampire
- Vampire Fledgling
- Novice [Mage]
- Apprentice [Mage]
Reanimate Corpse (up to 13):
- Bandit Thug
- Dremora Caitiff
- Blooded Vampire
- [Mage] Adept
Revenant (up to 21):
- Bandit Highwayman
- Bandit Plunderer
- Dremora Kynval
- Forsworn Looter
- Vampire Mistwalker
- [Mage]
Dread Zombie (up to 30):
- Bandit Marauder
- Bandit Chief
- Dremora Kynreeve
- Forsworn Pillager
- Vampire Nightstalker
- [Element] Wizard
- Ascendant [Mage]
Dead Thrall (up to 40):
- Dremora Markynaz
- Forsworn Ravager
- Ancient Vampire
- [Element]mancer
- Master [Mage]
Too Powerful to Raise
- Dremora Valkynaz
- Volkihar Vampire
- Arch [Mage]