Miasma
Medium-size Undead (Incorporeal)
Hit Dice:
3d12 (19 hp)
Initiative: +1 (Dex)
Speed: Fly 30 ft (perfect)
AC: 12 (+1 Dex, +1 deflection)
Attacks: Incorporeal touch +2 melee touch
Damage: Touch 1d4 Wisdom damage
Face/Reach: 5 ft. by 5 ft. /5 ft.
Special Attacks: Malevolence
Special Qualities: Incorporeal, undead
Saves: Fort +1, Ref + 2, Will +4
Abilities: Str -, Dex 13, Con -, Int 7, Wis 12, Cha 12
Skills: Hide +8, Intimidate +7, Listen +7, Spot +7
Climate/Terrain: Any land and underground
Organization: Solitary, swarm (2-5)
Challenge Rating: 3
Treasure: None
Alignment: Always chaotic evil
Advancement:  4-6 HD (Medium-size)
                        7-9 HD (Large)

Dark clouds of evil, fed by the nightmares of the dying and insane, these undead exist to propagate the horrific events that gave them birth.
     Miasmas look like rolling black mists.  They have no set form and create and absorb appendages constantly.  Only when they are about to take over a host will they develop any features, glowing red eyes that pierce the soul.
     Miasmas understand Common but can only speak it while in human form (they are also literate and enjoy writing disturbing messages in blood).

Combat
A miasma has one goal, to gain control of a mortal host.  It lashes out with its mist like tendrils attempting to sap an opponents will to the point where it will easily overcome their minds.  Once it gains control of a host it embarks on a murderous rampage.
  
Malevolence (Su): Once per round, the miasma can attempt to merge its body with an opponent.  This ability is similar to magic jar as cast by a 10th-level sorcerer, except that it does not require a receptacle.  If the attack succeeds the miasma vanishes into the creature�s body.  The target can resist the attack with a successful Will save (DC 16).
   
Incorporeal: Can be harmed only by other incorporeal creatures, +1 or better weapons, or magic, with a 50% chance to ignore any damage from a corporeal source.  Can pass through solid objects at will, and own attacks pass through armor. Always moves silently.
   
Undead: Immune to mind-influencing effects, poison, sleep, paralysis, stunning, and disease.  Not subject to critical hits, subdual damage, ability damage, energy drain, or death from massive damage.
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