The Final Chapter: From Flames and Frost

Now we get to the truly advanced parts of Necromancy. This is the level that 99% of Necromancers never attain (especially alive). Initially you have found and been taught that the Death Essence is the power of Necromancy. This is true, for Lesser Necromancy. As a warning: Lesser Necromancy is more than sufficient for almost every need. A competent Lesser Necromancer will be hard pressed to ever find a foe so powerful that they must resort to Greater Necromancy. Greater Necromancy need only be used in the most extreme situations!
This is the overwhelming power of Greater Necromancy: The Two Spheres. The two spheres are Fire and Ice, or what I call Hell and Styx.
Hell, thanks to Christianity, is well known to most people. It is the place where evil creatures, souls and spirits are confined to a burning inferno. Black lava rock, lava, demons, acidic and burning rain, ashes, fire, chains, torture, disfigurement and unspeakable pain are all components of that place. This is where the most vile of the Fire sphere are kept. When a Necromancer wishes to draw the most powerful servient entity they can muster, it is from Hell they come. Hell is the abode of already captive and tortured creatures, so all the Necromancer must do is promise a brief time of relaxation from the pain in exchange for services. Almost every being will gladly take such a trade in an instant. To do this, the Necromancer must use ether from Styx to cool the aura of the spirit and keep them bound to earth. From Hell, a Necromancer can call Minor Demons, Greater Demons (though not Satan or Archdemons), Fire Wraiths (quite a sight), Fire Skeletons and Hell Imps. This is an exhaustive list (as far as I can tell). The accessible content of Hell changes all the time though, so the availability of these creatures may fluctuate slightly. It is also the ether of Hell that allows a very skilled caster in Greater Necromancy to cast very un-Necromantic spells such as Fire Blast. Be careful when using Hell's fury though. Even though most creatures are willing to be servants for the price of temporary freedom, some of them will try to trick a Necromancer into making deals that are unbalanced and cost dearly.
Styx is the second of the spheres. It is where the most powerful of Necromantic creatures lie. Unlike Hell, however, the creatures of Styx are not always servient. Styx is the abode of Death himself. It is a cold place of silence, grief, mental pain and loss. It is the place of whispers, chill, cold swamps, dead trees, barren ground, cloudy skies, and ominous nothing. From here, Necromancers draws the most powerful entities available to them (not excluding Death). Creatures such as Undead Servitors, Wraiths, Spectres, Geists, Shadows, Death Steeds, Grim Reapers (there are many of them) and Death himself are available with enough coaxing and skill. The creatures of Styx have a desire, much like the creatures of Hell: They want to live again. Whereas Hell is full of sensation (albeit
painful), Styx is greviously lacking of sensation. The creatures of Styx want to be on earth again simply to be able to feel, and to interact with their enviroment. This is the bargaining tool of the Necromancer in this case. Using Hell's ether, a Stygian creature can be bound to earth to perform the Necromancer's will.
Now I'd like to avoid confusion about binding Hell or Styx creatures to earth; You do not always need to use ether from the opposite sphere to bind a creature to earth, though I have found that the method usually works. In this case, as in most things in the world, there are always exceptions to the rules. If one was to call Death, for instance, using Hell essence would be very bad. Death must remain in his own element, and therefore should be "bound" using only Death Essence or Styx power. The same goes for calling Reapers (or some types of Steeds). They are totally Stygian and therefore cannot be bound using Hell power. By the time a Necromancer reaches this level, being able to tell how to summon a creature will be second nature instead of a mystery (as it may seem now to some readers). As a last piece of advice on Greater Necromancy: Hell and Styx, though chock full of standard creatures, occasionally surprise me and spontaneously make bizarre creatures available for summoning. Sometimes, these creatures do not even seem like they belong in that particular sphere, but they appear nonetheless. Take advantage of these bizarre quirks, since they come along infrequently.
Now, with the dispensing of this knowledge, I call to a close the realm of Necromancy; the art of Necromancy has been covered to the fullest extent possible (without revealing anything that one must learn of their own accord). First, learning Lesser Necromancy and then learning Greater Necromancy, one has very little true opposition. Call the zombies, ghouls, wraiths, imps, servitors, demons and skeletons to sing their cacophony if ever you totally master Greater Necromancy; On that day the world will end, I'm sure...