Jellies...! Part 2

Working onwards from last week's post, I was wondering whether, if jellies are partially the result of magical experiments, what would happen if they had some magical abilities? With that in mind, here's another jelly design. It's statted for 1E AD&D and, as always, includes an illustrative doodle:

LIGHTNING JELLY

  
FREQUENCY: Rare
 
NO. APPEARING: 1
 
ARMOR CLASS: 8

MOVE: 3"

HIT DICE: 4-6

% IN LAIR: Nil

TREASURE TYPE: Nil

NO. OF ATTACKS: See below

DAMAGE/ATTACK: See below

SPECIAL ATTACKS: See below

SPECIAL DEFENSES: See below

MAGIC RESISTANCE: Standard

INTELLIGENCE: Non-

ALIGNMENT: Neutral

SIZE: M (6 feet wide, 2-3 feet high in spherical form)

PSIONIC ABILITY: Nil

       Attack/Defense Modes: Nil
 

Lightning jellies are found in dungeons and other subterranean places, usually taking on the appearance of a pool of water or of moisture running along a surface. Like the ochre jelly, it can squeeze through narrow spaces and can move along ceilings, walls, and floors.

It is only when attacking that the jelly takes on another form, gathering itself to become a spherical mass that has a slight blueish glow. It will then loose a charge of electricity, attacking as a 3rd level Magic User casting Lightning Bolt and inflicting 3-18 points of damage. It can usually only make one attack per turn, although striking the creature with lightning bolts only serves to give the jelly an extra attack in the following round. The jelly will absorb the organic part of any fallen prey.

Lightning jellies are immune to cold attacks but fire-based attacks have a normal effect.