Creature Catalogue: A little surprise for your wizards

Fa'au'ash
HD: 1*-9*****
AC: -2
MV: 90' (30')
AT: As Magicuser L1-9
DA: As Spells
SA: Magicuser L1-9
NA: 1(1)
ML: 12
TT: A/HD
INT: 18
AL: Chaotic
XP: 13xp-4,400xp

Description: An otherplanar horror that nests in crystal balls or uses them as planar gates. A Fa'au'ash is outside its nest a creature of enthropic smoke, invulnerable to magic weapons of +2 or less. They will attack with spells as a magicuser of level equal to Hit Dice, collect magic items and slip back into their nest.
A crystal ball that is nest to a Fa'au'ash will be a pocket dimension where the Fa'au'ash keeps all its treasures or a gate to the real nest. They can go unnoticed in a crystal ball for millenia. And there are rumors of 40HD Fa'au'ash out on the planes. PCs can enter the pocket plane and kill its nesting  Fa'au'ash claiming a Crystal ball with a pocket dimension. There is a 1% chance that a crystal ball is a nest to a Fa'au'ash.