Magical Beast animal companion advancement

[Natael]

I need to figure out how to advance my animal companion appropriately. Technically, my DM gave Rangers full AC progression, though that is irrelevant to the question.

So my 3rd level feat was Exalted Companion {pg 42, BoED}, at 4th level I picked myself up a blink dog, all good and happy. So now I'm 7th level and finally get those happy bonus hit dice. Reading into it I only get d8's instead of magical beast progression, then I see that my companion's BaB is based off the equivalent druid levels, so as I read this, my doggy's BaB would actually have dropped by becoming a companion and then got back to +4 as I get my next two bonus HD.

Is there an explanation or chart somewhere that I may have missed in regards to getting magical beasts as animal companions? Or is there just a rules gap for making magical beasts companions (as I didn't see any good explanation in the Eberron book under Totem Companion either)?

[RagnaroksChosen]

I need to figure out how to advance my animal companion appropriately. Technically, my DM gave Rangers full AC progression, though that is irrelevant to the question.

So my 3rd level feat was Exalted Companion {pg 42, BoED}, at 4th level I picked myself up a blink dog, all good and happy. So now I'm 7th level and finally get those happy bonus hit dice. Reading into it I only get d8's instead of magical beast progression, then I see that my companion's BaB is based off the equivalent druid levels, so as I read this, my doggy's BaB would actually have dropped by becoming a companion and then got back to +4 as I get my next two bonus HD.

Is there an explanation or chart somewhere that I may have missed in regards to getting magical beasts as animal companions? Or is there just a rules gap for making magical beasts companions (as I didn't see any good explanation in the Eberron book under Totem Companion either)?

I always assumed that if your AC was changed to something else via feat it progressed that type.
Also I assume that it wouldn't loose BAB?
I don't have the exhalted AC feat in front of me but doesn't it just let you take a magical beast as your AC? and it advances like normal no?

[phlidwsn]

Judging by the following FAQ entry for a Dire AC, I'd guess you progress them as a magical beast still, but its one of those fuzzy cases that's up to the DM

In the animal companion sidebar (PH 36), it says that
animal companions have good Fortitude and Reflex saves,
which are also the good saves for all regular animals.
However, dire animals have good progression in all three
saves. Thus, what happens when a dire animal becomes a
druid’s animal companion?
The line in question simply reiterates the normal rule for
animals for ease of play. Dire animals use their normal good
saves, even after becoming animal companions.

[ericgrau]

http://www.d20srd.org/srd/classes/druid.htm#theDruidsAnimalCompanion

Except for the different save progression of magical beasts and any exceptions noted in the feat, I think it should be the same.