Undead

On Spawn-creating Undead
Several kinds of undead create spawn when they kill a victim in a particular way (vampires, wraiths, shadows, etc). There is a popular perception that this creates a rules loophole whereby a low-level necromancer can pay a high-level spellcaster to, say, summon a shadow, have that shadow kill "a squirrel" (which will then rise as another shadow), and then rebuke the new shadow to get a start on his own army of the undead.

Firstly, it's important to point out that, Rules As Written, this will not work: the "create spawn" ability of the undead listed in the SRD specify that it only works on humanoids. However, a first-level commoner is an easy challenge also, isn't it?

Thus, the following addenda apply to all "create spawn" abilities: Exceptions:
 * 1) The victim must have at least as many Hit Dice as the undead creature's CR in order to rise. Thus, a level 3 commoner slain by a wight or a shadow would not rise.
 * 2) Undead creatures currently under the effects of a summon spell cannot create spawn.
 * 1) Vampires can create other vampires who are weaker than they are, and may create vampire spawn as they see fit; however, in order to create a vampire spawn from a creature with fewer than 4 HD, they must use their blood drain ability.
 * 2) Creatures slain by negative levels have a 50% chance of rising as a wight if they have fewer than 3 HD.
 * 3) Any "advanced" undead uses their base creature CR to determine how powerful a victim must be in order to become a spawn.