Highest Natural Armor Bonus

[Alistaroc]

Hey Playground, quick question.

Which creature of 24 HD or under(preferably 20 or under though) has the highest natural armor bonus, and is a form that could be wildshaped into as a Master of Many Forms?
Essentially anything but Outsiders, Elementals, and Undead.
Highest I've found so far is the Hive Mother Beholder, with +25 Natural Armor.

All sources are allowable for 3.5, Dungeon and Dragon Magazines yes, Pathfinder no.

[MisterKaws]

Well, Wyrmling Prismatic Dragon has 22 Natural armor, but it also has an innate 5 Deflection bonus, so it's kind of a 27.

It's a Cha-based SU, ignore me ;-;

Edit: Mature Shadow Dragon has 22hd and 25 nat as well, with lower dex, though it might be more useful if you wanna slap someone with a ton of natural attacks.

[Thurbane]

Dwarven Ancestor (http://archive.wizards.com/default.asp?x=dnd/ex/20060704a&page=3) used to rate pretty well for Outsiders with Alter Self (+18 natural armor bonus).