Vampire spawn are hideous undead creatures, created by vampire lords and ladies. Vampire spawn remain under the control of their vampire lord or lady until they are released and become full vampires in their own right. Vampire spawn are often sent on missions by their vampire masters.
LESSER VAMPIRE SPAWN
Armor Class: 5 
Hit Dice: 4
Attacks: Bite (1d6)
Saving Throw: 13
Special: Regeneration; Slow; Zombie Control
Move: 12/18 (Flying)
Challenge Level/XP: 6/400
Lesser vampire spawn are created by vampires to be servants until such time that they become full vampires. Despite the fact that lesser vampire spawn are weaker than their greater vampire spawn kin in many respects, they are not harmed by running water and sunlight. However, they are repelled by garlic and are turned by clerics as if they were shadows.
COMBAT: Lesser vampire spawn are not subject to fear and their behavior in combat is determined by their vampire masters.
REGENERATION: Lesser vampire spawn regenerate at 1 point per round. When the lesser vampire spawn reaches zero hit points or below, it is no longer able to regenerate.
SLOW: When a lesser vampire spawn successfully bites an opponent or victim, the opponent must make a saving thrown. If the saving throw is failed, the opponent is slowed. The opponent then moves and attacks at half speed for 2d4 rounds.
ZOMBIE CONTROL: A lesser vampire spawn can control up to 4 zombies at a time.
GREATER VAMPIRE SPAWN
Armor Class: 4 
Hit Dice: 6
Attacks: Bite (1d8)
Saving Throw: 11
Special: Regeneration; Level Drain; Zombie Creation & Control
Move: 12/18 (Flying)
Challenge Level/XP: 8/800
Greater vampire spawn are created by vampires to be servants until such time that they become full vampires. Greater vampire spawn turn into a gaseous form and return to their vampire master. Greater vampire spawn can only be killed in the same manner as a vampire: By sunlight, by running water, or by a wooden stake driven into its heart. They are repelled by garlic and are turned by clerics as if they were wraiths.
COMBAT: Greater vampire spawn are not subject to fear and their behavior in combat is determined by their vampire masters.
REGENERATION: Greater vampire spawn regenerate at 2 points per round. When the greater vampire spawn reaches zero hit points or below, it is no longer able to regenerate. It becomes gaseous and returns to its master, where it regains its body after a time of rest.
LEVEL DRAIN: When a great vampire spawn successfully bites an opponent, the opponent must make a saving throw. If the saving throw is failed, the bitten opponent loses one experience level.
ZOMBIE CREATION & CONTROL: An opponent that dies by the bite of a greater vampire spawn becomes a zombie under the control of the greater vampire spawn, one round after death. A greater vampire spawn can control up to 10 zombies at a time.
I am working on a small sandbox setting for an occasional Pits & Perils game with my wife. I had posted about it a few weeks ago, but do not have much new to add. My wife reads my blog and I do not want to be posting spoilers since we are doing a mystery-based campaign.