How I Stopped Worrying and Learned to Love Eberron
The art of sustaining life where there is none. Necromancy is an ancient art, defying the cycle of life where the dead decay and are reintroduced into the ecosystem. Undead creatures last years beyond their expiration date, and sometimes centuries. The necromancer collects energy and infuses the corpse with artificial life to restart it, but the creature must often be sustained afterwards.
In Eberron, necromancers use the vast energy reservoirs of Mabar and Irian, negative and positive planes, respectively.
Public perception of necromancy is generally negative, but there are significant exceptions. The Blood of Vol holds up necromancy as a valiant sacrifice for Seekers to support their faith indefinitely. Karrnathi citizens understand the necessity of their standing undead army in the face of powerful enemies. And the elven nation of Aerenal hold positively-charged necromancy in the highest regard, keeping their greatest leaders in a constant state of undeath.